KR100925071B1 - Thin-wall bearing - Google Patents

Abstract

The retainer 4 of the thin-film bearing was a split retainer constituted by a plurality of resin plate members 5, 5, ... made of a curved shape along the inner ring 1 and the outer ring 2. The holder 4 has a pocket 6 which opens at an axial end and protects the ball 3 so as to be electrically driven, and has a pillar between the adjacent pockets 6, 6 ( In the central portion of 10), a slit-shaped through hole 14 extending in the axial direction and opening at the axial end of the side where the opening 7 of the pocket 6 is located is formed. Therefore, the thin film bearing has good lubricity.

Thin film bearing, rolling element, retainer, inner ring, outer ring

Description

Thin Film Bearings {THIN-WALL BEARING}

The present invention relates to a thin film bearing.

Although thin film bearings are used for robots for semiconductor manufacturing apparatuses, etc., since these robots are normally used in a vacuum environment, thin film bearings also become a specification for vacuum. For example, inner ring and outer ring are martensitic stainless steel such as SUS 440C, and martensite stainless steel such as SUS 440C or ceramics such as silicon nitride and silicon carbide, and retainer is brass, SUS 304, SUS 316 or the like. Fluorine grease is used as a lubricant, and especially in an environment in which outgassing is avoided, a lubricating film containing a fluorine-containing polymer and fluorine oil having a functional group, and a lubricating oil and a fluorine resin containing alkylated cyclopentane or polyphenyl ether as main components. Lubrication coatings containing are suitable.

In addition, a thin film bearing is a bearing with a large inner diameter compared with thickness, and in this invention, the rolling bearing which satisfy | fills following formula is made into a thin film bearing. In the formulas described below, D is the outer diameter and d is the inner diameter.

 (D-d) /d≤O.187

As a retainer of such a thin-film bearing, in general, since the retainer is mounted after the rolling element is assembled between the inner and outer rings, the opening 104 for inserting the rolling element (ball, 102) into the pocket 103 has a shaft. The ring-shaped holder 101 which has the edge part of the direction is used (refer FIG. 7-9). The opening width of the opening 104 is smaller than the diameter of the rolling element 102, and a so-called Patin stand is provided, and the opening 104 is formed by the rolling element 102 when the rolling element 102 is inserted into the pocket 103. Is elastically widened to pass through the opening 104 (see FIG. 8). After insertion, the opening 104 elastically returns to its original state (see FIG. 9). This is because, in order for the rolling element 102 inserted into the pocket 103 to deviate from the holder 101, the rolling element 102 needs to elastically widen the opening 104 and pass therethrough. Needless to say, if the rolling element 102 easily deviates from the retainer 101.

However, in the case of the thin-film bearing, when the retainer is made of metal, the rolling element tends to slip out of the pocket of the retainer, so that a retainer made of resin is often used to suppress it. Below, the reason why a rolling element tends to be out of the pocket of a holder when a holder is made of metal is demonstrated.

Since the thin film bearing has a thin bearing, the diameter of the rolling element is smaller than that of a general bearing. However, since it is necessary to apply a load to the rolling element of small diameter, it is necessary to increase the number of rolling elements. During the rotation of the bearings, each rolling element is usually in various motion states, and sometimes a state in which a plurality of rolling elements are pushed from each other on both sides of a pillar of a retainer between them. At that time, the retainer is pushed to the inner and outer rings by the moving rolling elements, but when the number of rolling elements pushing each other is increased, the portions to be pushed and slide are increased. If so, the frictional force of the slide becomes large, and the retainer cannot follow the idle of the rolling element, so that the rolling element comes out of the pocket and the retainer jumps out of the bearing.

In the retainer made of resin, even if the retainer cannot follow the revolution of the rolling element, it deforms locally and absorbs energy. Therefore, compared with the metallic retainer, the rolling element comes out of the pocket and the retainer springs out of the bearing. It is hard to happen.

In such a case, a resin-made retainer is often used for the thin film bearing, but has the following problems. That is, although the resin retainer is manufactured by injection molding, there are many thin film bearings of different types and sizes, and therefore, it is impossible to manufacture a mold for each bearing in terms of cost.

Thus, the following technique has been adopted to solve this problem. That is, the resin plate-shaped member 201 having the pocket 203 capable of protecting and holding the rolling element in a rotatable manner is curved along the inner ring and the outer ring, and the plurality of the curved plate-shaped member 201 is inner ring. And a plurality of plate-like members 201 arranged along the outer ring, and having the same function as the annular holder shown in FIG. 7 (see FIG. 10). There is also a technique in which the elongate one plate-shaped member 301 is curved to form an retainer (see FIG. 11). In addition, in the following description, the retainer which comprised the several plate-shaped member shown in FIGS. 10 and 11 in an annular manner, and the retainer which comprised the one plate-shaped member curved to annular are described as "segment retainer." Sometimes.

According to this technique, it is necessary to manufacture one type of plate-shaped member by injection molding or compression molding, and to use a suitable number of plate-shaped members according to the type and size of the thin-film bearing, so that a mold must be produced for each bearing. There is no cost advantage. In addition, the above-mentioned plate-shaped member can also be manufactured by making an elongate strip | belt-shaped member by injection molding or compression molding, and cutting this.

12 (the above figure is a perspective view of the retainer, and the lower figure is a sectional view seen from the side where the axial opening 404 is located) between the adjacent pockets 403. The pillar 410 in the side is wider because of the parting band, and toward the axial end of the side where the opening 404 is located. When the retainer 401 is taken out of the mold after molding, the wide part 412 springs back, and the circumferential end portion 412a of the wide part 412 extends radially outward of the retainer 401. It may deform so as to protrude (in the following description, the portion deformed so as to protrude may be referred to as an “extrusion deformable portion”).

This occurs because the circumferential end portions 412a and 412a are attracted to each other by the tensile stress remaining in the wide portion 412. In particular, in the case of the division holder, since the plate-shaped member is bent by heating in the mold, springback of the wide portion is likely to occur.

While the outer diameter surface of the retainer slides with the outer ring during the rotation of the thin-film bearing, if the deformation occurs at the circumferential end of the wide portion by the spring back, the protruding deformation portion slides with the outer ring and wears out. And since the abrasion powder which generate | occur | produced absorbs the base oil of a lubricant, there exists a possibility that the lubricity of a thin film bearing may fall.

In addition, when using a parting retainer, as shown in FIG. 13, the circumferential edge part of the plate-shaped member 421 contacts the inner ring 422 or the outer ring 423 at the time of rotation of a membrane bearing, and slides. The circumferential end of the plate-like member 421 has a corner portion, and since the corner portion contacts the inner ring 422 or the outer ring 423, the surface pressure is increased and the circumferential direction of the plate-shaped member 421 is increased. The end is easily worn and wear powder is generated. Since the generated wear powder absorbs the base oil of a lubricant, there exists a possibility that the lubricity of a thin film bearing may fall.

Then, this invention solves the problem which the said prior art has, and makes it a subject to provide a thin-film bearing with favorable lubricity.

In order to solve the said subject, this invention consists of the following structures. That is, the thin film bearing of the present invention has a plurality of rolling elements disposed so as to be rotatable between the inner ring and the outer ring and the inner ring and the outer ring, and a pocket for opening the shaft in an axial direction to protect and keep the rolling element rotatably. In the thin-film bearing provided with the retainer made of resin, and satisfying the following formula, a through hole is provided in the pillar of the retainer.

 (D-d) /d≤O.187

In the formula, D is the bearing outer diameter, and d is the bearing inner diameter.

Here, the through hole is preferably a slit shape. Moreover, it is preferable that the said through hole is a hole opened in an axial end or a hollow hole which does not open in an axial end.

Furthermore, it is preferable that the said retainer is comprised by the 1 or more plate-shaped member arrange | positioned annularly along the said inner ring and the said outer ring. It is preferable to provide a chamfer in the circumferential edge part of this plate-shaped member. Moreover, it is preferable that the said plate-shaped member arrange | positions both plate surfaces toward the said inner ring and the said outer ring, respectively, and the said chamfer is formed so that the thickness of the said plate-shaped member may become thin gradually toward the said circumferential edge part. The chamfered portion is preferably curved or planar.

Furthermore, an edge portion formed at the boundary between the circumferential end face of the plate member and the chamfer portion is an edge portion formed at the boundary between the plate surface of the plate member and the chamfer portion without contacting the inner ring and the outer ring. Alternatively, the chamfered portion is preferably in contact with the inner ring or the outer ring.

Furthermore, at least one of the raceway surface of the inner ring, the raceway surface of the outer ring, and the raceway surface of the rolling element may be covered with any one of the following three types of lubricating coatings.

(1) A lubricating film containing a fluorine-containing polymer having a functional group and a perfluoropolyether

(2) A lubricating film containing a fluorinated polymer having a functional group, a perfluoropolyether, and a fluororesin

(3) Lubrication coating containing lubricating oil mainly composed of alkylated cyclopentane or polyphenyl ether and fluorine resin

Moreover, the thin-film bearing of this invention is equipped with the holder which has an inner ring, an outer ring, the some rolling element arrange | positioned between the said inner ring and the outer ring so that rotation is possible, and the pocket which protects and protects the said rolling element rotatably. And the holder is constituted by one or more resin plate-like members made annularly disposed along the inner ring and the outer ring, and the circumference of the plate-shaped member in the thin film bearing satisfying the following expression. A chamfer is provided in the direction end part.

 (D-d) /d≤0.187

In the formula, D is the bearing outer diameter, and d is the bearing inner diameter.

It is preferable that this plate-shaped member is arrange | positioned toward both the said inner ring and the said outer ring, respectively, and the said chamfer is formed so that the thickness of the said plate-shaped member may become thin gradually toward the said circumferential edge part. The chamfered portion is preferably curved or planar.

Further, an edge portion formed at the boundary between the circumferential end face of the plate member and the chamfer portion is an edge formed at the boundary between the plate surface of the plate member and the chamfer portion without contacting the inner ring and the outer ring. Preferably, the portion or the chamfered portion comes into contact with the inner ring or the outer ring.

Further, at least one of the raceway surface of the inner ring, the raceway surface of the outer ring, and the raceway surface of the rolling element may be covered with any one of the following three kinds of lubricating films.

(1) A lubricating film containing a fluorine-containing polymer having a functional group and a perfluoropolyether

(2) A lubricating film containing a fluorinated polymer having a functional group, a perfluoropolyether, and a fluororesin

(3) Lubrication coating containing lubricating oil mainly composed of alkylated cyclopentane or polyphenyl ether and fluorine resin

1 is a front view illustrating the structure of the thin film bearing of the first embodiment.

2 is a perspective view showing the structure of a plate-shaped member.

It is a perspective view and sectional drawing explaining the pillar vicinity part of a holder.

4 is a perspective view of a holder in which the through hole is a hollow hole.

It is a figure which shows the planar chamfer part formed in the plate-shaped member.

It is a figure which shows the curved-shaped chamfer formed in the plate-shaped member.

7 is a perspective view showing a general retainer used for a thin film bearing.

Fig. 8 is a view showing a state in which the rolling element is inserted into the pocket from the opening of the holder.

9 is a diagram illustrating a state in which a rolling element is inserted into a pocket of a holder.

10 is a perspective view showing a conventional dividing holder.

11 is a perspective view showing a conventional dividing holder.

It is a perspective view and sectional drawing explaining the part of the pillar vicinity of the conventional holder.

It is a figure which shows the edge part of the circumferential edge part of a plate-shaped member contacting an inner ring and an outer ring at the time of rotation of a thin film bearing.

It is a front view explaining the structure of the thin film bearing of 2nd Embodiment.

15 is a perspective view illustrating the structure of a plate-shaped member.

It is a figure which shows the planar chamfer part formed in the plate-shaped member.

It is a figure which shows the curved-shaped chamfer formed in the plate-shaped member.

It is explanatory perspective view for demonstrating the rolling bearing which is an example of 3rd Embodiment.

It is a perspective view for demonstrating a flat member.

It is explanatory drawing for demonstrating the relationship of length L and thickness t in the longitudinal direction of a flat member.

21 is a perspective view showing a retainer used in a conventional rolling bearing.

It is a perspective view which shows a mode that a rolling element is inserted into a pocket part from the opening part of a holder.

It is a perspective view which shows the state in which the rolling element was inserted in the pocket part of the holder.

It is explanatory drawing for demonstrating the holder of another conventional example.

It is explanatory drawing for demonstrating the holder of another conventional example.

It is a longitudinal cross-sectional view which shows the thin film rolling bearing of 4th Embodiment.

It is a schematic diagram explaining the structure of the apparatus for evaluating oscillation property.

It is a graph which shows the evaluation result of oscillation property.

It is sectional drawing of the rolling bearing of A of 5th Embodiment which provided the lubricating film.

It is an enlarged schematic diagram which shows the formation state of the lubricating film of A of 5th Embodiment.

(A) is a figure explaining a bearing rotation tester, (b) is a graph which shows the result of an oscillation amount test.

(A) is a figure which shows the outgas velocity test apparatus, (b) is a graph which shows the result of an outgas velocity test.

33 is a graph showing the results of the torque endurance test.

It is a figure explaining the linear guide apparatus which applied this invention.

It is a figure explaining the linear bearing which applied this invention.

It is a figure explaining the ball screw apparatus to which this invention is applied.

It is sectional drawing of the rolling bearing of B of 5th Embodiment which provided the lubricating film.

It is an enlarged schematic diagram which shows the formation state of the lubricating film of B of 5th Embodiment.

39 is a graph showing the results of the oscillation amount test.

40 is a graph showing the results of a torque endurance test.

It is a figure which shows the linear guide which is an example of the rolling support apparatus of 6th Embodiment.

It is a figure which shows the linear guide which is an example of the rolling support apparatus of 6th Embodiment.

It is a figure which shows the ball screw which is an example of the rolling support apparatus of 6th Embodiment.

It is a figure which shows the linear bush which is an example of the rolling support apparatus of 6th Embodiment.

It is a figure which shows the vacuum conveyance apparatus which is an example of the rolling support apparatus of 6th Embodiment.

It is a figure which shows the 2nd rolling bearing used for the vacuum conveyance apparatus shown in FIG.

Fig. 47 is a diagram illustrating a two-cylinder tester.

It is a partial longitudinal cross-sectional view which shows the structure of the angular ball bearing which is an example of the rolling bearing which concerns on 7th Embodiment.

(The best mode for carrying out the invention)

(First embodiment)

EMBODIMENT OF THE INVENTION Embodiment of the thin film bearing which concerns on this invention is described in detail, referring drawings. 1 is a front view showing the structure of the thin film bearing of the present embodiment, and FIG. 2 is a perspective view showing the structure of the plate-shaped member.

The thin-film bearing of FIG. 1 includes a plurality of balls 3 (only a part of which is shown) and balls arranged in a rotatable manner between an inner ring 1, an outer ring 2, and an inner ring 1 and an outer ring 2. A holder (4) for protecting and holding (3) so as to be rotatable, and a lubricant (not shown) such as lubricating oil and grease are provided, and the inner diameter d and the outer diameter D satisfy the following equation. do.

 (D-d) /d≤0.187

The retainer 4 is a split retainer, and has a pocket 6 capable of protecting and holding the ball 3 so as to be able to be electrically rotated, and a plurality of bents that are curved along the inner ring 1 and the outer ring 2 (example of illustration). In the case of eight) resin plate-shaped members 5, 5, .... That is, the plate-like members 5, 5,... Which are arranged toward the inner ring 1 and the outer ring 2, respectively, and which are arranged in an annular line along the inner ring 1 and the outer ring 2 are integral ring members. It has a function equivalent to the holder made of.

In addition, the circumferential length and the number of use of the plate-shaped member 5 are not specifically limited, The sum of the circumferential lengths of all the plate-shaped members 5, 5, ... is substantially the same as the circumferential length of a thin film bearing, What is necessary is just to set the circumferential length and the number of uses so that the majority of (3) can be protected and maintained in the pocket 6. If the above conditions are satisfied, the number of uses of the plate-shaped member 5 may be one (that is, the same thing as FIG. 11 mentioned above). In addition, the annular retainer which consists of one annular member can also be used for the thin film bearing of this embodiment instead of a parting retainer.

The opening part 7 for inserting the ball 3 into the pocket 6 is provided in the axial direction edge part of the plate member 5. The passage width of the opening 7 is smaller than the diameter of the ball 3, and a so-called Patin stand is provided, and when the ball 3 is inserted into the pocket 6, the opening 7 is burned with the ball 3. Sexually widened to pass through the opening (7). After the ball 3 is inserted, the opening 7 elastically returns to its original state.

In addition, as can be seen from FIG. 3 (the above figure is a perspective view of the retainer, and the lower figure is a sectional view seen from the side where the opening part 7 in the axial direction is located), the adjacent pocket 6, Between the pillars 6, one pillar 10 is wide because of the parting band, and toward the axial end of the side where the opening 7 is located (wide portion 12). In the central portion of the pillar 10, a slit-shaped (thin) through-hole 14 extending in the axial direction and opening at the axial end of the side where the opening 7 is located is formed.

When manufacturing the retainer 4, when the retainer 4 is taken out of the mold after molding the resin, the wide portion 12 springs back, and the circumferential ends 12a and 12a of the wide portion 12 are held. It may deform so that it may protrude in the radial direction outer side of the base 4. In particular, in the case of the split holder, since the plate-shaped member 5 is bent by heating it in a mold, spring back of the wide portion 12 is more likely to occur than the holder made of an integral annular member.

However, in the case of the retainer 4 of this embodiment, the through-hole 14 is provided in the column 10, and the tensile stress remaining in the wide part 12 is transmitted by the through-hole 14. Since it is not segmented and the circumferential edge parts 12a and 12a do not attract each other, spring back of the wide part 12 is unlikely to occur. Therefore, since hardly any projecting deformation occurs (see sectional view in FIG. 3), occurrence of wear powder due to wear of the circumferential end portion 12a of the wide portion 12 is suppressed, and as a result, the thin film bearing Excellent lubricity is easy to maintain.

In addition, the shape of the through hole 14 is not limited to the slit shape, but may be other shapes such as circular, elliptical, and spherical. In addition, as shown in Fig. 4, the through hole 14 may be a hollow hole which does not open in the axial end. In the case of the through hole 14 opening at the axial end as shown in FIG. 3, an edge portion is formed in the opening portion of the through hole 14, but the corner portion has an inner ring 1 or an outer ring 2 as compared with the flat portion. Abrasion by the slide is easy to occur. If the through-hole 14 is a hollow hole as shown in Fig. 4, no edge is formed, so wear is less likely to occur.

In addition, the both ends of the circumferential direction of the plate-shaped member 5 are chamfered, the edge part of a substantially right angle is removed, and the chamfer between the circumferential end surface 5a and the plate surface 5b of the plate-shaped member 5 is carried out. The base 5c is formed (refer FIG. 5). The chamfered part 5c is planar, and the chamfered part 5c is formed, and the thickness of the plate-shaped member 5 becomes thin gradually toward the circumferential edge part. And the edge part formed in the boundary of the circumferential end surface 5a of the plate-shaped member 5 and the chamfer 5c at the time of rotation of a thin-film bearing as adjusting the degree of curvature of the plate-shaped member 5, An inner ring 1 includes a corner portion or a chamfer 5c formed at the boundary between the plate surface 5b of the plate-shaped member 5 and the chamfer 5c without contacting the inner ring 1 and the outer ring 2. ) Or the outer ring 2. As shown in FIG. 6, the chamfer 5c may be curved.

Therefore, when the contact portion between the plate-shaped member 5 and the inner ring 1 or the outer ring 2 is an obtuse corner, the surface pressure is lowered, and the circumferential end of the plate-shaped member 5 becomes difficult to wear. And if the chamfer 5c is curved, surface pressure will become lower. As a result, since the amount of wear powder is reduced, the amount of base oil of the lubricant absorbed by the wear powder is also reduced, and the lubricity is less likely to occur. Moreover, since the chamfering part 5c exists, the base oil of a lubrication agent is attracted to the contact part with the inner ring 1 or the outer ring 2 by the plate-shaped member 5 easily, and wear is less likely to occur.

In addition, when the chamfer 5c has a planar shape, as shown in FIG. 5, the angle between the extension line of the chamfer 5c and the circumferential end surface 5a is 45 ° or more and less than 90 ° (ie, chamfer). The angle formed between the base 5c and the circumferential end surface 5a is preferably 90 ° or more and less than 135 °). In such a configuration, since the angle of the corner portion formed at the boundary between the plate surface 5b and the chamfer 5c of the plate-shaped member 5 becomes more obtuse, the plate-shaped member 5 and the inner ring 1 or the outer ring 2 ), The surface pressure at the contact portion with () becomes lower, and the circumferential end portion of the plate member 5 becomes more difficult to wear. Further, since the distance between the circumferential end of the plate-like member 5 and the inner ring 1 or the outer ring 2 becomes small, the contact portion between the plate-shaped member 5 and the inner ring 1 or the outer ring 2 is reduced. The base oil of the lubricant is more likely to be attracted.

This plate-shaped member 5 can be manufactured by the usual resin molding method, such as injection molding and compression molding. In addition, you may manufacture the plate-shaped member 5 by making a long strip | belt-shaped member by injection molding or compression molding, and cutting this. If the retainer 4 is manufactured in this way, the manufacturing cost of the thin film bearing becomes low.

Although the kind of resin material of the plate member 5 is not specifically limited, Polyamide paper, such as nylon 66 which is excellent in flexibility, is employ | adopted in many cases. Moreover, from low outgassing property, fluororesins, such as polytetrafluoroethylene and a polyether ether ketone, are also used. Furthermore, when thin film bearings are used under high temperature conditions, polyether ether ketones, polyimide resins, polyamide imide resins and the like which are excellent in wear resistance are used.

Such a thin film bearing of this embodiment can be used suitably for the robot etc. for semiconductor manufacturing apparatuses. Since the robot is usually used in a vacuum environment, the lubricant used for the thin film bearing is preferably for a high vacuum environment having low outgassing properties. The following three types of lubricating films (hereinafter referred to as DFO lubricants) have a lower outgassing property than fluorine grease, and thus are suitable for the thin film bearing of the present embodiment.

(1) A lubricating film containing a fluorine-containing polymer having a functional group and a perfluoropolyether

(2) A lubricating film containing a fluorinated polymer having a functional group, a perfluoropolyether, and a fluororesin

(3) Lubrication coating containing lubricating oil mainly composed of alkylated cyclopentane or polyphenyl ether and fluorine resin

Since lubrication using this DFO lubricant is lubrication by a thin film of lubricant, there is a problem that the lubricity is lower than when fluorine grease or the like is enclosed in a bearing. Therefore, when applied to the thin-film bearing using the conventional resin division holder, the circumferential edge part of a protrusion deformation | transformation part and a plate-shaped member tends to wear | wear, and lubricity fell further by abrasion powder. Therefore, it was often difficult to apply a DFO lubricant to a thin film bearing using a conventional resin retainer (particularly a retainer). However, in the thin film bearing of this embodiment, since wear hardly arises as mentioned above, DF0 lubricant can be applied without a problem.

Here, the DFO lubricant will be described. The DFO lubricant is a lubricant containing a fluorine-containing polymer and a fluorine oil (for example, perfluoropolyether (PFPE)) having a functional group having high affinity for metals, and having extremely high viscosity. The fluorine-containing polymer having a functional group adsorbs to the metal surface extremely strongly by the function of the functional group. On the other hand, the molecule | numerator of fluorine oil has the property of reattaching immediately even if it is once removed, for example, and it is hard to disperse | distribute. Therefore, it is excellent in low out gas property.

As a fluorine-containing polymer which has a functional group, a fluoro polyether polymer and a poly fluoro alkyl polymer are preferable. As a fluoropolyether polymer, the polymer of the number average molecular weights 1000-50000 which has a repeating unit represented by following General formula (1) is mentioned. In addition, this fluoropolyether polymer has the functional group mentioned later at least in one molecule terminal.

(Formula 1)

-C _X F _2X -O- (X is an integer from 1 to 4)

In addition, examples of the polyfluoroalkyl polymer include those shown in the following general formula (2). Y in the formula (2) is a functional group having a high affinity for a metal, and for example, an epoxy group, an amino group, a carboxyl group, a hydroxyl group, a mercap group, an isocyanate group, a sulfone group, an ester group, and the like are preferable. As a polyfluoroalkyl polymer, what is shown, for example in Formula (3) and (4) besides what is shown by General formula (2) can be used suitably.

(Formula 2)

(Formula 3)

(Formula 4)

When the functional group is coated with the surface of the inner ring or outer ring when the DFO lubricant is coated on the inner ring or outer ring surface, a lubricating film strongly bonded to the inner ring or outer ring surface is formed. In the case of a fluorine-containing polymer having a plurality of functional groups in one molecule, at least one of them may be combined with a metal. The said fluorine-containing polymer may be used independently of the above-mentioned, and may use 2 or more types together. When using 2 or more types together, it is preferable to select the combination so that the functional groups may react and the functional group couple | bonded with a metal will not reduce.

As a specific example of the fluorine-containing polymer which has such a functional group, For example, Klitox 157 FSL, 157 FSM, 157 FSH by DuPont, Gemnam modified product SA, SH, SY-3 by Daikin Industries Co., Ltd. Montane von Purin ZDEAL, ZDIAC, ZD ISCO, ZDOL, ZDOL TX2000 and the like.

In addition, although the kind of fluorine oil like PFPE is not specifically limited, In order to suppress outgas low, it is preferable to use the thing with as low vapor pressure as possible. Specifically, Clitox 143 AB, 143 AC, 143 AD of DuPont company, von Purin YHVAC 18/8, 25/9, 40/11, 140/13, Z25, Z60 of the Augmont company, S-65, S-100, S-200, etc. of Daikin Industries Co., Ltd. are mentioned.

As a specific example of a DFO lubricant containing a fluorine-containing polymer having a functional group and a fluorine oil such as PFPE, S-200 of Daikin Industries Co., Ltd. as a PFPE is used as a fluorine-containing polymer having a functional group therein. 5% of FSH is added, and it diluted with 2% with the fluorine-type solvent (For example, AK225 made by Asahi Chemical Co., Ltd.).

In addition, when the powder of the fluororesin is added, the DFO lubricant can be made lower in dusting. In addition, by using lubricating oil mainly composed of alkylated cyclopentane or polyphenyl ether instead of fluorine oil, the thin film bearing can have a longer service life. As alkylated cyclopentane, a tri (2-octyl dodecyl) cyclopentane is mentioned, for example.

Such DFO lubricant may be enclosed in a bearing inner space formed between the inner ring and outer ring of the thin-film bearing, but is coated on the raceway surface of the inner ring or outer ring and then dried by heating, decompression, etc. to form a lubricating film. desirable.

(Second embodiment)

EMBODIMENT OF THE INVENTION Embodiment of the thin film bearing which concerns on this invention is described in detail, referring drawings. FIG. 14 is a front view showing the structure of the thin film bearing of the present embodiment, and FIG. 15 is a perspective view showing the structure of the plate-shaped member. In addition, in each drawing referred to by 2nd embodiment, the same code | symbol as the case of 1st embodiment is attached | subjected to the angle degree same as the 1st embodiment, and the equivalent.

The thin-film bearing of FIG. 14 includes a plurality of balls 3 (only a part of which is shown) and balls arranged in a rotatable manner between an inner ring 1, an outer ring 2, and an inner ring 1 and an outer ring 2. A holder (4) for protecting and holding (3) so as to be rotatable, and lubricants (not shown), such as lubricating oil and lubricating oil, are provided, and the inner diameter d and the outer diameter D satisfy the following equation. do.

 (D-d) /d≤O.187

The retainer 4 is a split retainer, and has a pocket 6 capable of protecting and holding the ball 3 so as to be able to be electrically rotated, and a plurality of bents which are curved along the inner ring 1 and the outer ring 2 (example of illustration). In the case of eight) resin plate-shaped members 5, 5, .... That is, the plate-shaped members 5, 5,... Which are arranged toward the inner ring 1 and the outer ring 2, respectively, and which are arranged in an annular line along the inner ring 1 and the outer ring 2 are annular. It is equivalent to the retainer. In addition, the circumferential length and the number of use of the plate-shaped member 5 are not specifically limited, The sum of the circumferential lengths of all the plate-shaped members 5, 5, ... is substantially the same as the circumferential length of a thin film bearing, What is necessary is just to set the circumferential length and the number of uses so that the majority of (3) can be protected and maintained in the pocket 6. If the above conditions are satisfied, the number of uses of the plate-shaped member 5 may be one (that is, the same thing as FIG. 11 mentioned above).

The opening part 7 for inserting the ball 3 into the pocket 6 is provided in the axial direction edge part of the plate member 5. The opening width of the opening 7 is smaller than the diameter of the ball 3, and a so-called patine stand is provided. When the ball 3 is inserted into the pocket 6, the opening 7 is burned with the ball 3. Sexually widened to pass through the opening (7). After the ball 3 is inserted, the opening 7 elastically returns to its original state.

In addition, the both ends of the circumferential direction of the plate-shaped member 5 are chamfered, the edge part of a substantially right angle is removed, and the chamfer between the circumferential end surface 5a and the plate surface 5b of the plate-shaped member 5 is carried out. The base 5c is formed (refer FIG. 16). This chamfer 5c is planar, and the chamfer 5c is formed, and the thickness of the plate-shaped member 5 becomes thin gradually toward the circumferential edge part. And the edge part formed in the boundary of the circumferential end surface 5a of the plate-shaped member 5 and the chamfer 5c at the time of rotation of a thin-film bearing as adjusting the degree of curvature of the plate-shaped member 5, An inner ring 1 includes a corner portion or a chamfer 5c formed at the boundary between the plate surface 5b of the plate-shaped member 5 and the chamfer 5c without contacting the inner ring 1 and the outer ring 2. ) Or the outer ring 2. As shown in FIG. 17, the chamfer 5c may be curved.

Therefore, when the contact portion between the plate-shaped member 5 and the inner ring 1 or the outer ring 2 is an obtuse corner, the surface pressure is lowered, and the circumferential end of the plate-shaped member 5 becomes difficult to wear. And if the chamfer 5c is curved, surface pressure will become lower. As a result, since the amount of wear powder is reduced, the amount of base oil of the lubricant absorbed by the wear powder is also reduced, so that deterioration of lubricity is unlikely to occur. In addition, since the chamfering part 5c exists, the base oil of a lubrication agent is attracted easily to the contact part with the inner ring 1 or the outer ring 2 by the plate-shaped member 5, and abrasion hardly arises.

Moreover, when the chamfer 5c is planar, as shown in FIG. 16, the angle which the extension line of the chamfer 5c and the circumferential end surface 5a makes is 45 degrees or more and less than 90 degrees (that is, chamfering). The angle formed between the base 5c and the circumferential end surface 5a is preferably 90 ° or more and less than 135 °). In such a configuration, since the angle of the corner portion formed at the boundary between the plate surface 5b and the chamfer 5c of the plate-shaped member 5 becomes more obtuse, the plate-shaped member 5 and the inner ring 1 or the outer ring 2 ), The surface pressure at the contact portion with () becomes lower, and the circumferential end portion of the plate member 5 becomes more difficult to wear. Further, since the distance between the circumferential end of the plate-like member 5 and the inner ring 1 or the outer ring 2 becomes small, the contact portion between the plate-shaped member 5 and the inner ring 1 or the outer ring 2 is reduced. This makes it easier to draw the base oil of the lubricant.

This plate-shaped member 5 can be manufactured by the usual resin molding method, such as injection molding and compression molding. In addition, you may manufacture the plate-shaped member 5 by making a long strip | belt-shaped member by injection molding or compression molding, and cutting this. If the retainer 4 is manufactured in this way, the manufacturing cost of the thin film bearing becomes low.

Although the kind of resin material of the plate member 5 is not specifically limited, Polyamide paper, such as nylon 66 which is excellent in flexibility, is employ | adopted in many cases. Moreover, from low outgassing property, fluororesins, such as polytetrafluoroethylene and a polyether ether ketone, are also used. Furthermore, when thin film bearings are used under high temperature conditions, polyether ether ketones, polyimide resins, polyamide imide resins and the like which are excellent in wear resistance are used.

Such a thin film bearing of this embodiment can be used suitably for the robot etc. for semiconductor manufacturing apparatuses. Since the robot is usually used in a vacuum environment, the lubricant used for the thin film bearing is preferably for a high vacuum environment having low outgassing properties. The following three types of lubricating films (hereinafter referred to as DFO lubricants) have a lower outgassing property than fluorine grease, and therefore are suitable for the thin film bearing of the present embodiment.

(1) A lubricating film containing a fluorine-containing polymer having a functional group and a perfluoropolyether

(2) A lubricating film containing a fluorinated polymer having a functional group, a perfluoropolyether, and a fluororesin

(3) Lubrication coating containing lubricating oil mainly composed of alkylated cyclopentane or polyphenyl ether and fluorine resin

Since the lubrication using this DFO lubricant is lubrication by a thin film of the lubricant, there is a problem that the lubricity is lower than when fluorine grease or the like is encapsulated in the bearing. Therefore, when applied to the thin film bearing using the conventional resin part retainer, the circumferential edge part of a plate-shaped member is easy to wear, and lubricity fell further by abrasion powder. Therefore, it was often difficult to apply a DFO lubricant to a thin film bearing using a conventional resin divider holder. However, in the thin film bearing of this embodiment, since abrasion powder is hard to generate | occur | produce as mentioned above, a DFO lubricant can be applied without a problem.

Here, the DFO lubricant will be described. The DFO lubricant is a lubricant containing a fluorine-containing polymer and a fluorine oil (for example, perfluoropolyether (PFPE)) having a functional group having high affinity for metals, and having extremely high viscosity. The fluorine-containing polymer having a functional group adsorbs to the metal surface extremely strongly by the function of the functional group. On the other hand, the molecule of fluorine oil also has a property of reattaching immediately even after being removed once, and thus it is difficult to dissipate. Therefore, it is excellent in low out gas property.

As a fluorine-containing polymer which has a functional group, a fluoro polyether polymer and a poly fluoro alkyl polymer are preferable. As a fluoropolyether polymer, the polymer of the number average molecular weights 1000-50000 which has a repeating unit represented by following formula (5) is mentioned. In addition, this fluoropolyether polymer has the functional group mentioned later at least in one molecule terminal.

(Formula 5)

-C _X F _2X -0- (X is an integer from 1 to 4)

In addition, examples of the polyfluoroalkyl polymer include those shown in the following formula (6).

Y in the formula (6) is a functional group having a high affinity for a metal, and for example, an epoxy group, an amino group, a carboxyl group, a hydroxyl group, a mercap group, an isocyanate group, a sulfone group, an ester group, and the like are preferable. As the polyfluoroalkyl polymer, ones shown in the general formula (6), for example, in addition to those shown in the general formula (6) can be suitably used.

(Formula 6)

(Formula 7)

(Formula 8)

When the functional group is coated with the surface of the inner ring or outer ring when the DFO lubricant is coated on the inner ring or outer ring surface, a lubricating film strongly bonded to the inner ring or outer ring surface is formed. In the case of a fluorine-containing polymer having a plurality of functional groups in one molecule, at least one of them may be combined with a metal. The said fluorine-containing polymer may be used independently of the above-mentioned, and may use 2 or more types together. When using 2 or more types together, it is preferable to select the combination so that the functional groups may react and the functional group couple | bonded with a metal will not reduce.

As a specific example of the fluorine-containing polymer which has such a functional group, For example, Klitox 157 FSL, 157 FSM, 157 FSH by DuPont, Gemnam modified product SA, SH, SY-3 by Daikin Industries Co., Ltd. And montane von purine ZDEAL, ZDIAC, ZDISCO, ZDOL, ZDOLTX 2000.

In addition, although the kind of fluorine oil like PFPE is not specifically limited, In order to suppress outgas low, it is preferable to use the thing with as low vapor pressure as possible. Specifically, Clitox 143 AB, 143 AC, 143 AD of DuPont company, von Purin YHVAC 18/8, 25/9, 40/11, 140/13, Z 25, Z 60 of the Augmont company And S-65, S-100, S-200, etc. of Daikin Industries Co., Ltd. are mentioned.

As a specific example of a DFO lubricant containing a fluorine-containing polymer having a functional group and a fluorine oil such as PFPE, S-200 of Daikin Industries Co., Ltd. is used as PFPE, and Clytox of DuPont Company is a fluorine-containing polymer having a functional group therein. 5% of 157 FSH is added, and this is diluted to 2% with a fluorine-based solvent (for example, AK 225 from Asahi Chemical Co., Ltd.).

In addition, when the powder of the fluororesin is added, the DFO lubricant can be made lower in dusting. In addition, by using lubricating oil mainly composed of alkylated cyclopentane or polyphenyl ether instead of fluorine oil, the thin film bearing can have a longer service life. As alkylated cyclopentane, a tri (2-octyl dodecyl) cyclopentane is mentioned, for example.

Such DFO lubricants may be enclosed in the bearing inner space formed between the inner ring and outer ring of the thin-film bearing, but they may be coated on the raceway surface of the inner ring or outer ring and then dried by heating, decompression or the like to form a lubricating film. desirable.

(Third embodiment)

This embodiment is related with the rolling bearing used for a semiconductor manufacturing apparatus etc., for example, and relates especially to the rolling bearing of thin film suitable for use in a lean lubrication environment.

First, lean lubrication and thin film rolling bearings will be described. Lean means that there is little oil without waste, and lean lubrication means a method of lubricating only the raceway surface of a bearing with a very small amount of necessary minimum lubricant (oil or lubricant). . Since there are few lubricants, the temperature rise which arises from the resistive force when a rolling element advances in a lubricant becomes small, and the abnormality of the mechanical precision resulting from temperature becomes small. In addition, during the rotation of the bearing, the lubricant itself is sprinkled up and scattered by the passage of the rolling element, and the surrounding environment may be contaminated. However, in the case of lean lubrication, the lubricating film is originally very thin. The amount of lubricant to scatter is a very small amount, and the pollution of the environment is at least minimized.

As a specific example of lean lubrication, a lubricant is supplied during rotation of a bearing such as oil plating, grease plating, etc., in which a lubricant is applied in advance (DFO lubrication is also one kind), oil air lubrication, or oil mist lubrication. To form a solid lubricating film on the raceway surface by sputtering MoS ₂ , polytetrafluoroethylene (PTFE) -containing composite plating, PTFE-containing resin coating, etc., PTFE-containing resin retainers, rolling elements and rolling elements And a method of transferring a lubricant by sliding a member containing a lubricant, such as a resin member containing MoS ₂ , charged between the rolling element and the like.

Next, the rolling bearing of thin film is a shape whose bearing cross section is close to square, and the inner diameter dimension of a bearing is large compared with the thickness dimension of a bearing, and a so-called Cadon type corresponds to this. The ratio of the bearing thickness and inner diameter of the smallest inner diameter of NBX 2504 in the NBX type in the catalog of the N series thin film bearings manufactured by Seiko Kogyo Co., Ltd. is about 0.187, and 0.025 in the inner diameter of the large NBX 101625. If it is defined using the numerical value, the rolling bearing of the thin film is defined as a bearing having a ratio of the bearing thickness dimension and the bearing inner diameter dimension of 0.187 or less.

In the case of using a retainer in such a rolling bearing of such a thin film, in general, since the retainer is mounted after the rolling element is assembled between the inner and outer rings, as shown in Figs. 21 and 22, the rolling element is disposed at the end in the axial direction. A ring-shaped retainer 501 having an opening 504 for inserting 502 (ball) into the pocket portion 503 is used. In addition, the "thickness" here is a half value of the difference in the inner and outer diameter dimensions of a bearing.

The opening part 504 is provided with a parting stand, and when the rolling element 502 is inserted into the pocket part 503, as shown in FIG. 22, the opening part 504 is elastically widened by the rolling element 502. As shown in FIG. By passing the opening part 504, the rolling element 502 is inserted into the pocket part 503, and after insertion, the opening part 504 elastically returns to an original position (refer FIG. 23). In order for the rolling element 502 inserted into the pocket 503 to escape from the retainer 501, the rolling element 502 needs to elastically widen the opening 504 and pass therethrough once again. Originally, the rolling element 502 does not easily escape from the holder 501 with this structure. The material of the retainer 501 is made of metal, and usually is made of brass or stainless steel.

However, in the conventional thin film rolling bearing, the following problems may occur when used in a lean lubrication environment. That is, although the outer diameter part and the inner diameter part of the retainer may slide with the outer ring or the inner ring during bearing rotation, in a rich lubrication environment in which grease is present, the retainer wears a lot by the slide with the outer ring or the inner ring. There is no work. However, in lean lubrication, the retainer wears in a large amount, and the wear powder is passed between the raceway surface and the rolling element, and the rotational performance of the bearing may be significantly reduced.

In addition, thin-film rolling bearings have a small bearing thickness, so that the rolling element diameter is generally smaller than the bearing inner diameter compared to the case of a general bearing. From the need to receive, the number of rolling elements loaded between inner and outer rings cannot be helped. For example, in a rolling bearing with a thinner inner diameter of about 200 mm in diameter, 80 or more rolling elements are loaded. During rolling of the bearing, the individual rolling elements are in various states of motion, and are pushed together via a retainer. I'm in a bad situation.

In this case, under a rich lubrication environment, the friction coefficient is small even when a slide is generated between the rolling element and the retainer pocket, so that the retainer is hardly pushed in a direction other than the rotational direction by the force from the rolling element. In a lean lubrication environment, the friction coefficient between the rolling element and the retainer pocket is not small, so that the force from the rolling element presses the retainer in a direction other than the rotational direction.

And in some cases, the force of the force from the rolling element which the whole retainer receives acts in the direction which disengages a retainer from a rolling element, and the force is the vocalization of the part of 1 or 2 retainer pocket part. If there is more than the force equivalent to the force, the rolling element will come off from one or two retainer pockets. Then, it propagates in turn, and a phenomenon occurs that the rolling element deviates from the retainer pocket and finally comes out of the bearing about half of the circumference of the retainer. Thus, in order to eliminate such inadequacy, it is conceivable to use a retainer made of resin.

When the resin retainer is used with lean lubrication, the force from the rolling element does not displace the entire retainer in a direction other than the rotational direction due to the elasticity and flexibility of the resin, and part of the retainer is bearing. It is possible to prevent the problem of jumping out of the cylinder and also to reduce the surface pressure even when a slide between the retainer and the inner and outer rings occurs, thereby preventing the retainer from being worn in large quantities.

However, in order to make the resin retainer ring-shaped, first, it is necessary to mold the ring-shaped member by injection molding, and it is a burden on the cost for the injection molding die to be produced at every bearing number. In fact, DFO lubrication furnace, which is the best of lean lubrication, also has a name number that is limited in manufacturing number, such as thin film rolling bearings for semiconductor manufacturing equipment used in a vacuum environment. It is difficult to manufacture a molding die.

Therefore, the following technique is adopted as the next best solution. First, as shown in FIG. 24, the elongate belt-shaped holder member 506 which has the some pocket part 503 which protects and rolls a rolling element is prepared. This retainer member 506 is produced by injection molding or compression molding. If the retainer member 506 is used, for example, for a bearing having a pitch circle diameter of about 200 mm, the inner diameter of the outer diameter dimension of about 200 mm and the diameter larger by the thickness of the retainer than the inner mold. The outer shape of the holder is prepared, and the retainer member 506 is loaded in the gap formed between the inner shape and the outer shape. The length of the retainer member 506 to be loaded is cut and adjusted to a predetermined position in accordance with the size of the bearing.

Next, the retainer member 506 is protected and held for a predetermined time at a predetermined annealing temperature depending on the type of resin in a state of being charged between the inner mold and the outer mold. For example, the resin is protected at 150 ° C. for 30 minutes in case of nylon 66, and maintained at 230 ° C. for 3 hours in case of PEEK. Although this step is called heat setting, the holding member 506 is shaped into a ring shape by this heat setting, and retains its shape even when taken out of the mold, and is used as the ring holder 507. .

In addition, when the size of a bearing is large and one circumferential length is insufficient in one retainer member 506, as shown in FIG. 25, the one retainer member 506 which is not cut | disconnected, for example, is cut | disconnected. By adjusting the length by a plurality of pieces, for example by combining the retainer member 506a of about half length, it can respond also to the retainer longer in circumferential length than the one retainer member 506. Even if a thin-wall rolling bearing generally has a different inner diameter, if it is the same series, if the bearing thickness is the same and if only a circumferential length can be adjusted by a retainer, it can apply all in a series. In the method of opening and retaining the retainer member 506 as a ring-shaped retainer, even if the order numbers are different, the same retainer member can be used for all light numbers in the series as long as there is only the heat-setting inner shape and the outer shape. It is not necessary to separately manufacture the injection molding dies, and it is advantageous in terms of cost.

However, in the conventional method, the retainer member 506 is heat-fixed to form a ring-shaped retainer. In the case where the material of the retainer member 506 is PEEK or the like, it is the worst, at 230 ° C. for 3 hours. Protection and maintenance are necessary, and actually, before the process of protecting and holding the retainer member 506 between the internal shape and the external shape, the temperature rise to the temperature and the slow cooling after the protection and maintenance process are necessary. . Therefore, there is a problem that it takes 8 hours or more to finish one lot of processes, consumes considerable effort, power and time, and becomes expensive. In addition, since the belt-shaped retainer member 506 is bent by heat setting, the retainer may deform due to spring back or deformation may occur over time when the bearing is used at high temperature, and furthermore, the belt-shaped retainer member may occur. By bending 506, the pocket portion 503 or the opening portion 504 are widened outward and deformed.

SUMMARY OF THE INVENTION The present invention has been made to address such inadequacies, and even when used in a lean lubrication environment, a part of the retainer can be prevented from jumping out of the bearing and the retainer wears in large quantities. It is an object of the present invention to provide a rolling bearing that can be configured to retain the holder by using the same plate-like member for all bearings in the series, as well as for preventing it. Furthermore, an object of the present invention is to provide a rolling bearing capable of eliminating the bending process of the retainer, reducing the cost, and preventing deformation of the retainer and the retainer pocket.

MEANS TO SOLVE THE PROBLEM In order to achieve the said objective, this invention is a rolling bearing arrange | positioned so that a plurality of rolling elements can be rotated in a circumferential direction between a outer ring and an inner ring via a retainer, and the pocket part which protects and maintains the rolling elements so that rolling is possible. The plurality of resin plates are arranged in the circumferential direction to constitute the holder.

Here, when the length of the said plate-shaped member is set to L, the thickness of the said plate-shaped member is t, the inner diameter dimension of the said outer ring is D, and the inner diameter dimension of the said inner ring is d, t <0.5 (D It is preferable to satisfy the relationship of ² -L ² ) ^1/2 -0.5d.

Furthermore, it is preferable that the lubrication means is DFO lubrication. The DFO lubrication referred to in the present invention includes any one or both of a lubricating component having adsorptiveness and a solid lubricant in the thin film by oil plating, and specifically, the method described in Japanese Patent Laid-Open No. 2001-254803. Can be illustrated. There are various forms depending on the combination of the base oil, the lubricating component and the solid lubricant, or the film thickness. For example, DFO containing PTFE powder as a base oil, and a synonymized, low-life DFO using a synchropentane (hydrocarbon oil) as a base oil. An oscillating DFO and the like can be exemplified.

According to the present invention, since a plurality of flat plate-shaped members made of resin having pockets for protecting and rolling the rolling element are arranged in the circumferential direction to constitute a holder, even when used in a lean lubricating environment, the resin The elasticity and flexibility of the rolling element prevent the force from the rolling element from displacing the plate-shaped member constituting the retainer in a direction other than the rotational direction, and preventing a part of the retainer from jumping out of the bearing. Even when a slide between the resin flat member and the inner and outer rings constituting the retainer is generated, the surface pressure is reduced, so that the flat member can be prevented from being worn in large quantities.

Further, since a plurality of resin members are arranged in the circumferential direction to form a retainer, the retainer can be configured using the same flat member for all bearings in the series, and the flat member is bent. The heat setting step is unnecessary, and as a result, the cost can be reduced. In addition, since the heat-setting process for bending the flat plate member with an arc is unnecessary, the flat plate member can be deformed by spring back or deformed over time when the bearing is used at a high temperature. It spreads outward and can prevent deformation.

Further, when the length of the plate-like member is L, the thickness of the plate-shaped member t, the inner diameter of the outer ring D, and the inner diameter of the inner ring d, t <0.5 (D ² -L ^2). Satisfies the relationship of ^1/2 -0.5d, and it is possible to prevent one flat member from sliding at three points with respect to the outer ring and the inner ring at the same time, so that abrasion does not occur in the flat plate member.

EMBODIMENT OF THE INVENTION Below, an example of embodiment of this invention is described with reference to drawings. 18 is an explanatory perspective view for explaining a rolling bearing which is one example of an embodiment of the present invention, FIG. 19 is a perspective view for explaining the flat plate-like member, and FIG. 20 is a length L and a thickness in the long direction of the flat plate-shaped member. It is explanatory drawing for demonstrating the relationship with (t). Moreover, in this embodiment, the rolling bearing of the thin film (for example, ratio of a bearing thickness dimension and a bearing inner diameter dimension of 0.187 or less) used in the lean lubrication environment demonstrated previously is taken as an example.

The rolling bearing 510 which is an example of embodiment of this invention is a some rolling body (not shown) arrange | positioned between the outer ring 511 and the inner ring 512, as shown to FIG. 18 and FIG. : In this embodiment, the resin flat plate-like member 515 which has the retainer 513 which protects and maintains the ball) in the circumferential direction, and the pocket part 514 which protects and protects the said rolling element so that rotation is possible. ) Are arranged in the circumferential direction. As shown in FIG. 19, the flat member 515 has an opening 516 for inserting the rolling element into the pocket 514 on one side in the width direction, connected to the pocket 514. The opening 516 is provided with a parting stand. Then, the opening 516 is elastically widened by the rolling element to pass the opening 516 so that the rolling element is inserted into the pocket 514 and the opening 516 is elastically returned to its original position after insertion. .

Moreover, the plate-shaped member 515 is arrange | positioned in multiple numbers so that all the perimeters of the circumferential direction of the clearance gap between the outer ring 511 and the inner ring 512 may be filled, and the number of the required rolling elements is secured by this. . Further, circular arcs 517 having the same R as the circle of the pocket portion 514 are formed at both ends of the plate-shaped member 515 in the longitudinal direction, and between the plate-shaped members 515 neighboring each other in the circumferential direction. One rolling element is disposed, and arcs 517 formed at both ends of the plate-like member 515 in the longitudinal direction serve as pocket portions of the rolling element.

As the resin material of the flat member 515, for example, nylon, PEEK, or the like is used. In addition, phenol resins, epoxy resins, PES, PPS, PEI, PAI and the like can be exemplified. In this embodiment, the length of the plate-shaped member 515 in the longitudinal direction is L, the thickness of the plate-shaped member 515 is t, the inner diameter of the outer ring 511 is D, and the inner ring 512 is formed. When the outer diameter dimension is d, one flat member 515 has an outer ring 511 and an inner ring 512 such that the relationship of t <0.5 (D ² -L ² ) ^1/2 -0.5d is satisfied. We do not let you slide to three points at the same time.

More specifically, referring to FIG. 20, one flat plate holder 513 disposed between the outer ring 511 and the inner ring 512 has both ends at the inner diameter surface of the outer ring 511, and the center portion at the inner ring 512. If it is in the arrangement | positioning state which contacts the outer diameter surface of (), following Formula (1) is established.

(D / 2) ² = (L / 2) ² + (t + (d / 2)) ² . (One)

When (1) is summed up, it becomes following formula (2), (3).

D ² -L ² = 4 (t + (d / 2)) ² . (2)

(D ² -L ² ) ^1/2 = 2 (t + (d / 2))

         = 2t + d... (3)

Therefore, t = 0.5 ((D ² -L ² ) ^1/2 -d) and the condition that one flat member 515 does not slide to three points at the same time with respect to the outer ring 511 and the inner ring 512. Becomes the following equation (4).

t <0.5 ((D ² -L ² ) ^1/2 -d) = 0.5 (D ² -L ² ) ^1/2 -0.5d... (4)

That is, in the formula (4), if t is smaller than the right side, one flat member 515 does not slide to three points at the same time with respect to the outer ring 511 and the inner ring 512. That is, the plurality of plate-shaped members 515 constituting the retainer 513 are not subjected to bending, which is caused by one plate member 515 sliding to three points at the same time with respect to the outer ring 511 and the inner ring 512. 515 moves without contacting the gap between the outer ring 511 and the inner ring 512 at three points at all times. As a result, abrasion can be prevented from occurring in the flat member 515.

As described above, in this embodiment, a plurality of resin plate members 515 made of resin having low hardness and low rigidity are disposed in the circumferential direction between the outer ring 511 and the inner ring 512 in the circumferential direction. 513, the DFO lubrication is the most important of the lubrication lean lubrication method using the retainer 513 in the thin film rolling bearing for semiconductor manufacturing apparatus used in a vacuum environment. Also in this case, the elasticity and flexibility of the resin prevent the force from the rolling element from displacing the flat member 515 constituting the retainer 513 in a direction other than the rotational direction. Can be prevented from jumping out of the bearing. In addition, even when a slide occurs between the resin-like flat member 515 and the outer ring 511 and the inner ring 512 that constitute the retainer 513, the surface pressure decreases, so that the flat member 515 Wear can be prevented in large quantities.

In addition, since the resin plate | plate member 515 is arrange | positioned in the circumferential direction, and the holder 513 is comprised, it is not necessary to prepare an injection molding die every time, and the same plate for all bearings in a series is performed. The retainer 513 can be configured using the shape member 515. Furthermore, the heat setting process for bending the flat plate member 515 is unnecessary. As a result, the cost of the holder 513 can be reduced. In particular, rolling bearings are lubricated by DFO lubrication, which is the most important of lean lubrication, and in rolling bearings of limited number, such as thin film rolling bearings for semiconductor manufacturing apparatuses used in a vacuum environment, The holder 513 can be used suitably.

Furthermore, since the heat-setting process for bending the flat plate member 515 in an arc shape becomes unnecessary, the flat plate member 515 deforms with spring back or deforms over time when the bearing is used at a high temperature. It is possible to prevent the pocket portion 514 and the opening portion 516 from being widened outward and deformed rather than bending. In addition, the length in the longitudinal direction of the flat member 515 is L, the thickness of the flat member 515 is t, the inner diameter of the outer ring 511 is D, and the inner diameter of the inner ring 512 is d. When satisfying the relationship of t <0.5 (D ² -L ² ) ^1/2 -0.5d, one flat member 515 simultaneously has three points for the outer ring 511 and the inner ring 512. You can prevent it from sliding. As a result, the flat member 515 can move the gap between the outer ring 511 and the inner ring 512 in the circumferential direction without causing bending stress, thereby causing wear on the flat member 515. Can be avoided.

In addition, this invention is not limited to the said embodiment, It can change suitably in the range which does not deviate from the summary of this invention. For example, in the said embodiment, although the rolling bearing of the thin film used in a lean lubrication environment was taken as an example, it is not limited to this. In some cases, the present invention may be applied to rolling bearings used in a rich lubricating environment, and the present invention may be applied to ordinary rolling bearings without being limited to thin film rolling bearings. In addition, the structures of the outer ring, inner ring, rolling element, retainer, pocket part, flat plate member, lubrication means, and the like exemplified in the above embodiment are arbitrary as long as the present invention can be achieved and are not limited.

(4th embodiment)

This embodiment relates to a thin film rolling bearing and has a part which is related to the bearing of 1st-3rd embodiment.

Background Art Conventionally, thin film rolling bearings used in semiconductor-related devices, robots, and the like have been used in many types of open type, and some of them have also been sealed. In addition, a thin film rolling bearing means that bearing cross-sectional ratio (alpha) is 0.2 or less. Bearing section ratio (alpha) is defined by the following formula | equation.

α = (Dd) / (2 × D _PW )

In the above formula, D is the bearing outer diameter, d is the bearing inner diameter, and D _PW is the center diameter of the rolling element of the bearing.

Although grease is mainly used for lubrication of such thin-film rolling bearings, in the case of open-type thin-film rolling bearings, grease on the raceway is pushed out of the bearing by the retainer or the rolling element when the bearing rotates or leaked by centrifugal force. There was a concern. Moreover, also in the case of the sealed thin film rolling bearing, there was a possibility that lubricating oil leaked between the sealing lip and the outer diameter surface of the inner ring.

Therefore, Japanese Patent Laid-Open No. 2003 329049 discloses a thin-film rolling bearing which solves the above problems and makes maintenance free by enclosing a solid lubricant therein.

However, when lubricating a mixture of a polymer material composed mainly of polyolefin with a lubricant and using it as a lubricant, leakage of the lubricant is unlikely to occur, but since the absolute amount of the lubricant component is large, There existed a problem that a large amount of outgas was easy to generate | occur | produce. In addition, in the case of a solid lubricant, although lubricating oil is supplied by sliding a lubricant in contact with a rolling element or a raceway surface, it had the problem that an amount of oscillation increases by this sliding contact.

When a lubricating film made of a solid lubricant such as molybdenum disulfide (MaS), graphite, hexagonal boron nitride (h-BN), or graphite fluoride is coated on the raceway surface, there is little outgas, but wear is easy and durability is insufficient. There was a concern.

Therefore, the present invention solves the problems of the prior art as described above, and provides a thin film rolling bearing which is difficult to generate oscillation or outgas, hardly leaks of lubricant, and is excellent in durability and maintainable. do.

In order to solve the said subject, this invention consists of the following structures. That is, the thin film rolling bearing according to the present invention includes a plurality of rolling elements disposed so as to be rotatable between the inner ring, the outer ring, and the inner ring and the outer ring, and has a bearing cross-sectional ratio of 0.2 or less in the thin film rolling bearing. At least one of the raceway surface of the inner ring and the raceway surface of the outer ring is coated with a lubricating film made of a lubricant mixed with a fluorine resin in a base oil containing at least one of fluorine oil, alkylated cyclopentane, polyphenyl ether, and ester oil. It is characterized by one.

When such a lubricating film is provided, the contact between metals is suppressed during rolling operation of the rolling element, and low dust and stable lubricity are exhibited. That is, since a lubricating film consists of a lubricating agent which mixed fluororesin with base oil, it does not run out of lubricating oil (base oil) in a track surface, and exhibits stable lubricity. In addition, the excess lubricant (base oil) is trapped in the fluorine resin, so it is low in dust and less likely to leak the lubricant. In addition, the fluorine resin is more preferably in powder form.

Moreover, it is preferable that the film thickness of the said lubricating film is 0.1 micrometer or more and 10 micrometers or less. In order to reduce the amount of oscillation and the amount of outgas, the film thickness of the lubricating film is preferably small. However, in order to make the thin film rolling bearing excellent in durability, the film thickness is preferably large. In consideration of the balance of both, it is preferable that the film thickness of the lubricating film is 0.1 μm or more and 10 μm or less.

The thin film rolling bearing of the present invention hardly generates oscillation and outgas, and also less leakage of lubricant, and is excellent in durability.

Embodiment of the thin film rolling bearing which concerns on this invention is described in detail, referring drawings. It is a longitudinal cross-sectional view which shows one Embodiment of the thin film rolling bearing which concerns on this invention.

The thin film rolling bearing 601 of FIG. 26 includes an inner race 611 having a raceway surface 611a on its outer circumferential surface, an outer race 612 having an raceway surface 612a opposite to the raceway surface 611a on its inner circumferential surface, and The holding | maintenance which protects and maintains the several rolling elements 613 (ball) arrange | positioned so that rotation is possible between the track surfaces 611a and 612a, and the several rolling elements 613 between the inner ring 611 and the outer ring 612. A group 614 is provided. Moreover, the bearing cross-sectional ratio (alpha) represented by the above-mentioned formula of this thin film rolling bearing 601 is 0.2 or less.

Furthermore, at least one of both raceway surfaces 611a and 612a is a lubricating film (not shown) made of a lubricating agent comprising a fluorine resin mixed with a fluorine oil, an alkylated cyclopentane, a polyphenyl ether, and a base oil containing at least one of ester oils. This is covered.

Since the thin film rolling bearing 601 of this embodiment is lubricated with the lubricating film as mentioned above, even if it is not provided with a seal etc., it is hard to generate | occur | produce oscillation and outgas, and also it is hard to produce a leakage of a lubrication agent. Moreover, it is excellent in durability, and maintenance-free is possible. Therefore, it can use suitably also in a vacuum environment and a clean environment. Moreover, since the rotational resistance of a bearing is extremely small compared with the case of lubricating using a lubricating oil, high precision rotational performance can be obtained.

Moreover, it is preferable to form a minimum required lubricating film on the raceway surface of the inner ring, the raceway surface of the outer ring, the raceway surface of the rolling element, and the slide portion of the retainer. Then, oscillation by the extra lubricating oil (base oil) etc. can be suppressed. In addition, when a low lubricating oil (base oil) having a vapor pressure is used, generation of outgases can be suppressed.

The kind of the fluororesin is not particularly limited, but polytetrafluoroethylene (hereinafter referred to as PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene-ethylene air Copolymer (ETFE), tetrafluoroethylene hexafluoropropylene copolymer (FEP), and polychlorotrifluoroethylene (PCTFE) are preferable, and PTFE is most preferable among them.

In addition, the fluorine resin is more preferably in a powder form, and the particle diameter thereof is preferably from micron order to micron order. Moreover, the film thickness of this lubricating film is not particularly limited, but considering the balance between the suppression of oscillation and outgas and the durability of the bearing, it is preferable to be 0.1 μm or more and 10 μm or less.

Next, base oil is demonstrated. Examples of the fluorine oil include fluoropolyether polymers and polyfluoroalkyl polymers, and may further contain such derivatives (having functional groups).

As the fluoropolyether polymer, a polymer having a repeating unit represented by the following formula (9) is preferable. And as for the number average molecular weight, 1000 or more and 50000 or less are preferable. As the derivative of the fluoropolyether polymer, one in which the functional group having a high affinity for the metal is bonded to the fluoropolyether polymer. As an example of a functional group, an epoxy group, an amino group, a carboxyl group, a hydroxyl group, a mercap group, a sulfone group, and an ester group are mentioned.

Formula 9

-C _X F _2X -0- (X is an integer from 1 to 4)

In addition, examples of the polyfluoroalkyl polymer include those shown in the following general formula (10). Y in a formula is a functional group with high affinity with respect to the metal as mentioned above.

Formula 10

As the polyfluoroalkyl polymer, in addition to those shown in the formula (10), for example, those shown in the following formulas (11) and (12) can be suitably used.

Formula 11

(Formula 12)

Examples of commercially available fluorinated oils having such functional groups include Klytox 157 FSL, 157 FSM, 157 FSH from DuPont Corporation, Gemnam Modified Products SA, SH, SY-3, SP, and Solvay Recsys Co., Ltd. Von Purin Z DE AL, Z DIAC, Z DISCO, Z DOL, Z DOL TX2000, and the like.

Moreover, as perfluoro polyether (PFPE) oil which is a kind of fluoropolyether polymer, a commercial item can be used, For example, S-65, S-100, S-200 by Daikin Industries Co., Ltd., And von Purin Z-25, Z-60, 40/11 manufactured by Solvay Sole Resys Co., Ltd., and Klytox 16140 manufactured by DuPont Co., Ltd.

Furthermore, as alkylated cyclopentane, the tri (2-octyldodecyl) cyclopentane (for example, Synthetic Oil 2001A by Nye Lubricants), tri-n-octyl cyclopentane, tetra-n-octyl cyclopentane , Penta-n-octylcyclopentane, tri-n-nonyl cyclopentane, penta-n-decylcyclopentane, penta-n-dodecylcyclopentane and tetra-2-ethylhexyl cyclopentane. Since the alkylated cyclopentane has a low vapor pressure even in vacuum, even when the thin film rolling bearing of the present invention is used in vacuum, the base oil is difficult to evaporate and is a low out gas.

Furthermore, as polyphenyl ether, tetraphenyl ether, pentaphenyl ether, alkyl diphenyl ether, mono alkyl triphenyl ether, monoalkyl tetra phenyl ether, dialkyl tetra phenyl ether is mentioned, for example. Since such polyphenyl ether has a low vapor pressure and excellent heat resistance, the thin film rolling bearing of the present invention can be used in a vacuum or under a high temperature environment.

Furthermore, as ester oil, Nye Torr 5101 by Nye Lubricants company is mentioned, for example.

The inner ring 611, the outer ring 612, the rolling element 613, and the retainer 614 can all use a metal material that is generally used as a bearing material. For example, what performed the appropriate hardening heat treatment to the corrosion-resistant metal materials, such as martensitic stainless steels, such as JIS standard SUS 440C, and precipitation hardening stainless steels, such as JIS standard SUS 630, is mentioned. Moreover, if it is a light load application, what performed surface hardening processing to austenitic stainless steel and titanium alloys, such as JIS standard SUS304 and SUS 316, is suitable.

As the holder 614, brass, titanium and the like are suitably used in addition to the above metal materials, but a resin material may be used. As the resin material, for example, engineering such as fluorine resins such as PTFE and ETFE, polyether ether ketone resin (PEEK), polyphenylene sulfide resin (PPS), polyether sulfone resin (PES), polyamide resin and the like Plastics.

Such a resin material may contain the fibrous filler which improves mechanical strength, heat resistance, dimensional stability, etc. Although the kind of fibrous filler is not specifically limited, For example, aluminum borate whisker, potassium titanate whisker, carbon whisker, aramid fiber, aromatic polyimide fiber, liquid crystalline polyester fiber, graphite whisker, glass fiber , Carbon fiber, boron fiber, silicon carbide whisker, silicon nitride whisker, alumina whisker, aluminum nitride whisker, wollastonite.

The type of the retainer is not particularly limited and can be a waveform retainer, a tubular retainer, or the like. In addition, the holder 614 may not be provided.

In addition, this embodiment showed an example of this invention, and this invention is not limited to this embodiment. For example, in the present embodiment, a deep groove ball bearing has been described as an example of a thin film rolling bearing, but the present invention can be applied to various rolling bearings of different types. For example, radial rolling bearings such as angular ball bearings, self-aligning ball bearings, cylindrical rolling bearings, cone rolling bearings, needle-shaped rolling bearings and self-aligning rolling bearings, and thrust types such as thrust ball bearings and thrust rolling bearings. Is a rolling bearing.

(Example)

An Example is shown to the following and this invention is demonstrated further more concretely. Rolling bearings (example) substantially the same as the thin film rolling bearing 601 mentioned above, and the conventional thin film rolling bearings (comparative example) which enclosed fluorine grease were prepared, and each oscillation property was evaluated and compared. In addition, the thin-film rolling bearing of an Example and a comparative example is No. NBX 15206 (inner diameter (d): 152.4 mm, outer diameter (D): 165.1 mm, width: 6.35 mm, the center diameter of a rolling element) of the Seiko Co., Ltd. product. (D _PW ): 158.75 mm).

First, the thin film rolling bearing of an Example is demonstrated. The inner ring, outer ring, rolling element, and retainer are assembled to form rolling bearings for degreasing and washing. Then, a lubricant described later is supplied to the vicinity of the rolling element with a dropper or the like, the rolling bearing is rotated several times, and the lubricant is applied to the raceway surface of the inner ring, the raceway surface of the outer ring, the rolling surface of the rolling element, and the slide portion of the retainer. do. In addition, the method of attaching a lubricant is not limited to the application | coating method mentioned above, You may adhere by the spray method or the dipping method.

When the rolling bearing coated with lubricant is heated at 100 to 140 ° C. for 30 minutes and the diluting solvent contained in the lubricant is removed, the raceway surface of the inner ring, the raceway surface of the outer ring, the raceway of the rolling element, and the slide portion of the retainer, A lubricating film made of a lubricant is formed. Moreover, when baking process is further performed, since the outgas amount can be reduced more, it is preferable. The conditions of a baking process are pressure 10 Pa or less, temperature 1000 degreeC or more and processing time 4 hours or more, for example.

Next, the lubricant used for the thin film rolling bearing of an Example is demonstrated. The lubricant is mixed with 60 parts by mass of tri (2-octyldodecyl) cyclopentane (synthetic oil 2001A manufactured by Nye Lubricants) and 40 parts by mass of PTFE powder having a particle diameter of 1 μm or less, and 1 part by mass of the mixture, hexane and asahi-clean AK. 99 mass parts of dilution solvents, such as -225 (made by Asahi Glass Co., Ltd.), are mixed. As the PTFE powder, a dispersion in which the PTFE powder was dispersed in a solvent (dry film RA / IPA manufactured by DuPont) was used, and a PTFE powder dispersion having an amount such that the amount of the PTFE powder became the above numerical value was used.

Next, the evaluation method of oscillation property is demonstrated. The thin-film rolling bearings of Examples and Comparative Examples were assembled into the apparatus shown in Fig. 27, and driven over 24 hours under the following conditions, and the amount of oscillation generated therebetween was measured. In Fig. 27, reference numeral 621 denotes a test bearing, 622 denotes an axis, 623 denotes a moment load weight, and 624 denotes a coil spring for axial load.

Axial load: 18N

Moment load: 1 Nm

Actuator rocking angle: -60 ° ~ + 60 °

Actuation oscillation speed of actuator: 40 cycles / min

The test results are shown in the graph of FIG. In addition, the numerical value of the oscillation amount shown on the graph is shown by the relative value at the time of making the oscillation amount of the thin film rolling bearing of an Example 1. As can be seen from the graph, the thin film rolling bearing of the example was extremely low in the amount of oscillation at 1/20 as compared with the thin film rolling bearing of the comparative example in which fluorine grease was sealed.

Since the thin film rolling bearing of this invention can be used suitably also in a vacuum environment and a clean environment, it can be used suitably for conveyance apparatuses, such as a semiconductor manufacturing equipment, a liquid crystal panel manufacturing equipment, a hard disk manufacturing equipment, and a conveyance robot, for example. Do.

(5th embodiment)

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission device, and more particularly, to a transmission device in which lubrication is applied to a transmission site. Moreover, there is a part related to the bearing of 1st-4th embodiment.

Transmission apparatuses, such as a rolling bearing, a linear guide, a linear bearing, and a ball screw apparatus, may be used for the conveying system apparatus arrange | positioned, for example in the semiconductor manufacturing apparatus. The transmission device used in such a vacuum environment or in a clean atmosphere such as a clean room (hereinafter, also referred to as a "vacuum environment") is required in addition to smooth operation, high durability, and the like, and low dust generation.

For this reason, conventionally, by applying and enclosing a lubricant to the transmission site | part of a transmission apparatus, the wear of the rolling element and the site | part which contact | connects a rolling element is prevented, and smooth operation | movement is maintained.

In addition, in the above-mentioned vacuum environment in which contamination by oscillation or the like is hardly permitted, the transmission apparatus uses a fluorine-based lubricant based on fluorine-based lubricant having extremely low volatility, and thus the lubricant that is scattered or evaporated outside the transmission apparatus. The amount is suppressed.

Japanese Patent Laid-Open No. 173667 and Japanese Patent Laid-Open No. 62 246621 disclose examples of a transmission apparatus using such a fluorine-based lubricant. In such a transmission apparatus, a fluorine-type lubricant is affixed to a lubrication site | part, and the lubricating film which consists of said fluorine-type lubricant is formed. In addition, by using a fluorine-based lubricant having a functional group in the molecular structure as a fluorine-based lubricant and having a high affinity with the bearing material, a lubricating film that is strongly adsorbed to the bearing material is formed, thereby achieving low oscillation properties and durability.

In addition, Japanese Patent Application Laid-Open No. 284542 as an example of a fluorine-based lubricant shows a fluorine-based lubricant containing fluorine-based lubricant as base oil and polytetrafluoroethylene as a thickener. Furthermore, Japanese Patent Laid-Open Publication No. 13974 and Japanese Patent Laid-Open Publication No. 2002 357225 disclose examples of a transmission apparatus that encapsulates and uses a fluorine-based lubricant. Japanese Laid-Open Patent Publication No. 5,240257 discloses a rolling bearing using a fluorine-based solid lubricant mainly containing this polytetrafluoroethylene.

However, in the case where the fluorine-based lubricant is used, it is necessary to use a small amount of the fluorine-based lubricant in order to suppress external scattering, but in this case, the lack of lubrication action and the deterioration of durability cannot be avoided. On the other hand, although it is also considered to coat a rolling part with the said fluorine-type polymer solid lubricant, in the situation where a comparatively large axial load is applied, peeling or deficiency of a solid lubricant will occur, or since oscillation by abrasion will increase, durability and It may be insufficient in terms of low dust generation.

In addition, as described above, a method of improving low oscillation properties and durability by adhering a fluorine-based lubricant having a functional group in the molecular structure has been proposed, but the molecules chemically attached to bearing materials and the like are single molecular layers, The fluorine-based lubricant having a functional group of is not chemically attached. In general, the fluorine-based lubricant having a functional group has a higher vapor pressure as compared to the fluorine-based lubricant having no functional group. For this reason, outgas is easy to generate | occur | produce as the extra fluorine-type lubricating oil which does not adhere chemically evaporates. Furthermore, since the excess fluorine-based lubricant is also released as the oscillation particles, in order to use it in an environment where the organic contamination by the outgas or the oscillation is hardly tolerated, a countermeasure capable of suppressing the outgas and the oscillation more highly is required. In this respect, if there is no excess fluorine-based lubricating oil and only one molecular layer, the problem of the out gas or the like is eliminated, but the durability is inevitably insufficient.

The present invention has been made in view of the above-described problems, and an object thereof is to provide a transmission apparatus which can be suitably used in a vacuum environment or the like, has little dust and outgas generated in the apparatus, and has excellent durability. .

The transmission device of the present invention has an inner member having a raceway surface on its outer surface, an outer member disposed on the outside of the inner member with a raceway surface opposite to the raceway surface of the inner member, and between the raceways. In the transmission apparatus provided with the some rolling element arrange | positioned possibly, WHEREIN: At least one of the raceway surface of the said outer member, the raceway surface of the said inner member, and the raceway surface of the said rolling member is carried out at 20 degreeC by an oil plating process. A lubricating film formed of a lubricant containing a lubricating oil having a vapor pressure of 1 × 10 ⁻⁵ Pa or less and a fluororesin is formed.

Here, an oil plating process means the process for attaching a thin film to the track surface of the said outer member, the track surface of the said inner member, or the rolling surface of the said rolling element. For example, as described below, the lubricating film according to the present invention can be formed by attaching a diluted lubricant to the raceway or the like and removing the diluting solvent by heat treatment.

As a result of diligent research, the present inventors have found that it is effective to add a fluororesin to a lubricating oil for achieving low oscillation. When a lubricating film is formed with a lubricant containing a lubricating oil of 1 × 10 ^-5 Pa or less and a fluororesin at a vapor pressure of 20 ° C., the lubricant is always supplied to the raceway surface, and the raceway surface and the raceway surface do not directly contact each other. Since excess lubricant is trapped by the fluorine resin, the lubrication action is stably maintained with low oscillation and low outgas. In addition, unlike the solid lubricating film, the fluidity is maintained, so that peeling, deficiency and abrasion caused by wear in the solid lubricating film are suppressed. Furthermore, in forming a lubricating film by the oil plating process, since rotational resistance becomes extremely small compared with normal lubricating oil lubrication etc., high precision rotational performance can be obtained.

As mentioned above, the lubricating oil in this invention is 1 * 10 <^-5> Pa or less in vapor pressure at 20 degreeC, and the lower the vapor pressure, the less outgas is preferable. In addition, if the vapor pressure at 20 ° C. exceeds 1 × 10 ⁻⁵ Pa, the effect of suppressing the outgas cannot be sufficiently obtained even if a fluorine resin is added. Moreover, in the past, the lubrication film was formed to be thin, so that the oscillation and the out gas were suppressed by forming the lubrication film thinly. Therefore, durability can also be improved. That is, it is preferable to form a lubricating film to the extent which can cover the mountain of roughness in the surface which should form the said lubricating film, respectively. This is because when the lubrication film is thinner than this, part of the acid is easily exposed, the lubrication film is in a boundary lubrication state where the oil film on the other side in contact is easily received, and local flammability is easily generated. On the contrary, when the lubrication film becomes too thick, excess lubricant is likely to scatter, and the effect of suppressing the oscillation and the outgas is lowered. The thickness adjustment of such a lubricating film can be performed by adjusting the dilution density | concentration of the dilution solution of the lubricating agent which adheres to the surface which should form a lubricating film, for example in the oil plating process mentioned later.

As the fluorine resin, in addition to polytetrafluoroethylene (hereinafter abbreviated as PTFE), ethylene tetrafluoride perfluorovinyl ether copolymer (PFA), fluorinated ethylene propylene copolymer (FEP) and the like can be suitably used. .

In the transmission apparatus of this invention, it is preferable that the said lubricating oil is fluorine-type lubricating oil. When fluorine-based lubricating oil is used as the lubricating oil, there is little outgas since the volatility is extremely low. Moreover, in the transmission apparatus of this invention, it is preferable to make content of the said fluororesin in the said lubricant 5 mass% or more and 40 mass% or less. When the content of the fluorine resin is lower than 5% by mass, the dust suppression effect is deteriorated. When the content of the fluorine resin is higher than 40% by mass, the content of the lubricating oil is lowered, so the lubricity deteriorates. More preferably, they are 10 mass% or more and 30 mass% or less.

Further, in the transmission device of the present invention, the fluorine-based lubricating oil is 10 mass% or more and 98 mass% or less in the molecular structure and 90 mass% or less and 2 mass% or more in the molecular structure. It is preferable to construct.

As described above, by using a fluorine-based lubricant having a high affinity with materials constituting the raceway or the like as the fluorine-based lubricant and having a functional group in the molecular structure, a lubrication film that firmly adheres to the raceway or the like is formed, so that durability and dust suppression are suppressed. The effect can be improved. On the other hand, the fluorine-based lubricating oil having a functional group in the molecular structure is generally high in vapor pressure and easy to generate outgas, while maintaining the effect caused by firm adhesion to the material, while the amount of outgas according to the conditions of the environment used is used. It is preferable to adjust the content as much as possible.

That is, by adding the fluorine resin to the lubricant, the outgas can be suppressed more conventionally, but in an environment in which the demand for outgas suppression is more difficult, the composition as described above, that is, a fluorine-based compound having no functional group in the molecular structure It is preferable to form a fluorine-based lubricating oil with 10 mass% or more of lubricating oil and 98 mass% or less, and 90 mass% or less of fluorine-type lubricating oil which has a functional group in molecular structure.

Furthermore, in an environment where the demand for outgas suppression is more difficult, 50 mass% or more and 98 mass% or less of a fluorine-based lubricant having no functional group in the molecular structure, and 50 mass% or less and 2 mass% or more of the fluorine-based lubricant having a functional group in the molecular structure It is preferable to constitute a fluorine-based lubricant. Moreover, in the environment where the demand for out gas suppression is most difficult, it is preferable to suppress the outgas by adding fluorine resin using only the fluorine-based lubricant having no functional group in the molecular structure as the fluorine-based lubricant.

Moreover, in the transmission of this invention, it is preferable that the said lubricating oil contains alkylated cyclopentane or polyphenyl ether as a main component. Since the vapor pressure in 20 degreeC is 1 * 10 <^-5> Pa or less, the lubricating oil containing alkylated cyclopentane or polyphenyl ether as a main component has the effect of suppressing outgass also in vacuum. Moreover, these hydrocarbon lubricants are excellent in lubricity compared with fluorine lubricant oils, and make a transmission apparatus a long service life.

Moreover, in the transmission apparatus of this invention, it is preferable to make content of the said fluororesin in the said lubricant 5 mass% or more and 60 mass% or less. When the content of the fluorine resin is lower than 5% by mass, the oscillation inhibitory effect deteriorates. When the content of the fluorine resin is higher than 60% by mass, the lubricity deteriorates and the torque increases because the content of the lubricating oil is lowered. More preferably, they are 5 mass% or more and 40 mass% or less.

Moreover, in the transmission apparatus of this invention, the said lubricating film forms the said lubricating film by the lubricant dilution solution which consists of the said lubricating agent 0.5 mass% or more and 10 mass% or less and the dilution solvent 99.5 mass% or less and 90 mass% or more. It is preferable to form on the surface which should be made to adhere, to 50 degreeC or more and 250 degrees C or less, to heat 15 minutes or more and 300 minutes or less, and to remove the said diluting solvent.

By this oil plating process, the formation of the lubricating film which exhibits the said effect and effect is possible. In this case, when the content of the lubricant is lower than 0.5% by mass, the lubricating film adhered to the raceway surface and the raceway surface becomes too thin, so that the durability is insufficient as described above. On the other hand, if it is higher than 10% by mass, the lubricant dilution solution, uniform adhesion and workability are adversely affected, and the lubricating film becomes too thick, resulting in deterioration of the oscillation and suppression effect of the outgas as described above.

In addition, when heating temperature and heating time exceed said upper limit temperature and upper limit heating time, the lubricity of the lubricant which comprises a lubrication film deteriorates, and also the raceway surface of the inner member and outer member, or the rolling surface of a rolling element. Causes a decrease in hardness and dimensional change. Conversely, if the temperature is set too low or the heating time is too short, the dilute solvent cannot be completely removed. For this reason, at the time of an actual oil plating process, the heating temperature and heating time which are in said range and sufficient to remove the said dilution solvent are set according to the kind and content of the dilution solvent used. In addition, considering the material constituting the raceway or the like, for example, in the case of using quenched and tempered steel, the heating temperature and the heating time are set so as not to cause the hardness decrease and the dimensional change.

Here, as an adhesion method of the said lubricant dilution solution, application | coating, spraying, etc. are mentioned, for example. Or the method of pulling up after immersion in the said lubricant dilution solution can also be used. In this case, the assembled transmission may be immersed, or the assembly of the transmission may be immersed after forming a lubricating film.

Moreover, the said dilution solvent can be used as a lubricating oil and a solvent of both fluororesins, As a specific example, Novek (Sumitomo 3M Co., Ltd.) of an alternative freon type dilution solvent, perfluorocarbon (PFC), and a fluorine-type inert solution Products), Patrel (manufactured by DuPont) and Garden (manufactured by Auzimont). When using a hydrocarbon type lubricating oil, hexane etc. can also be used as a dilution solvent.

Further, in the transmission device of the present invention, the center line average roughness Ra of the raceway surface of the outer member and the raceway surface of the inner member is set to 0.02 µm or more and 0.2 µm or less, and the centerline average roughness of the transmission surface of the rolling element ( It is preferable to make Ra) 0.002 micrometer or more and 0.01 micrometer or less.

By setting it as such surface roughness, surface pressure of a contact surface can be suppressed and durability can be improved. In addition, by setting the surface roughness as described above, since the lubricating film is suppressed in a small amount, it is possible to prevent excess lubricating oil from scattering and to enhance the effect of suppressing the oscillation and the outgas.

Furthermore, the transmission of the present invention can be used in a vacuum or in a clean room. Since the amount of oscillation and the amount of outgas are very low, the transmission apparatus according to the present invention is suitable for use as a clean room in a vacuum or a precision machine manufacturing plant.

As described in detail above, according to the transmission device of the present invention, by forming a lubricating film made of a lubricant containing a lubricant and a fluorine resin, it is possible to suppress oscillation and outgas while maintaining high rotational performance. Excellent durability.

Next, an embodiment of the present invention will be described with reference to the drawings. In addition, in each drawing referred to in the following description, the part which is equivalent to the other figure in 5th Embodiment is represented by the same code | symbol.

(A of the fifth embodiment)

FIG. 29 is a cross-sectional view of a portion of the ball 713 serving as the rolling element of a rolling bearing 710 (transmission device) subjected to an oil plating process using a fluorine-based lubricant and a lubricant (fluorine-based lubricant) containing a fluororesin. . The rolling bearing 710 is provided with the outer ring 712 (outer side member), the inner ring 711 (inner side member), the ball 713, and the corrugated retainer 714 manufactured by press working.

More specifically, the outer ring 712, the inner ring 711, the ball 713, and the retainer 714 are formed of a metal material generally used for bearings, and for example, a metal material having corrosion resistance. Is formed by. Examples of this kind of metal material include bearing steel such as JIS standard SUJ 2, martensitic stainless steel such as JIS standard SUS 440C, precipitation hardening stainless steel such as JIS standard SUS 630, and carburizing treatment and nitriding treatment of such metal materials. The thing which performed suitable hardening heat processing, such as the coating process of diamond like carbon, etc. are mentioned.

Among the hard films obtained by the hardening heat treatment, the diamond-like carbon film is particularly preferable in that the diamond-like carbon film does not wear itself at high hardness and does not wear the counterpart material. Also suitable is diamond-like carbon in a form containing a metal element.

Although the film formation method of a hard film is not specifically limited, It can form into a film by methods, such as sputtering, plasma CVD, and ion plating. When the hard film is a diamond-like carbon film, an unbalanced magnetron sputtering method (a non-equilibrium sputtering method), which is a kind of sputtering, is suitable.

It is preferable that the film thickness of a hard film is 0.5 micrometer or more and 10 micrometers or less. If the film thickness of the hard film is less than 0.5 µm, wear resistance is not exhibited. On the other hand, when the film thickness of a hard film exceeds 10 micrometers, in addition to the possibility that a hard film will be broken by the internal stress of a hard film itself, film-forming cost becomes high and it is unpreferable. In particular, when the hard film is a diamond-like carbon film, it is more preferable to set the film thickness to 1 µm or more and 10 µm or less.

In addition, when the track wheel and the rolling element are steel products such as SUJ 2 and stainless steel, at least one selected from Cr, W, Ti, Si, Ni, Fe, and the like between the base layer of the steel product and the diamond-like carbon film. You may provide the intermediate | middle layer which consists of a kind of metal. Alternatively, an inclined intermediate layer made of the metal and carbon and having a carbon concentration increasing toward the diamond-like carbon film, which is the outermost layer, may be provided. It is preferable that the thickness of such an intermediate | middle layer and an inclination intermediate | middle layer is 0.1 micrometer or more and 5 micrometers or less.

If the rolling bearing is a light load application, for example, austenitic stainless steel such as JIS standard SUS 304 or SUS 316, or surface hardening treatment on titanium alloy can be used as the metal material. As the ball 713, ceramics such as silicon nitride, alumina, and zirconia can be used in addition to the metal material.

Among the metal materials and ceramics listed above, a material having corrosion resistance is preferably used. Particularly, martenite-based stainless steel is used for the outer ring 712 and the inner ring 711, and martensite-based for the ball 713. It is preferable to use stainless steel and ceramics. The reason is as follows. Usually, in order to give corrosion resistance to a rolling bearing, the method of adding a rust inhibitor to a lubricant is taken. By the way, since this rust inhibitor is easy to evaporate compared with the component of the fluorine-type lubricant which comprises the lubricating film of this invention, addition of a rust inhibitor becomes a factor which increases an oscillation and outgas. Therefore, when corrosion resistant materials are used for the inner ring 711 and the outer ring 712, the corrosion resistance can be realized, and the amount of lubricant used can be reduced, so that the oscillation and out gas suppression aimed at by the present invention can be achieved. have.

In addition to the metal material, brass, titanium, and the like are suitably used for the retainer 714, but a synthetic resin material may be used. As this synthetic resin material, for example, fluorine resins such as PTFE and ethylene tetrafluoroethylene (ETFE), polyether ether ketone (PEEK), polyphenylene sulfide (PPS), polyether sulfone (PES), nylon ( 46) it is also possible to use such as engineering plastics. Reinforcing fibers, such as glass fiber, may be added to such a synthetic resin material. The format of the holder 714 can also be tubular in addition to the waveform.

In this embodiment, the rolling bearing 710 has a contact surface (orbital surface) with the ball 713 of the outer ring 712, a contact surface (orbital surface) with the ball 713 of the inner ring 711, and a ball. On the rolling surface of 713, a lubricating film 715 made of a fluorine-based lubricant is formed by an oil plating process. FIG. 30 is an enlarged schematic diagram showing the formation state of a lubricating film on the raceway surface of the outer ring 712, the raceway surface of the inner ring 711, or the raceway surface of the ball 713. To the rolling bearing 710 shown in FIG. 30 to the extent beyond the calculation line of roughness in the surface D which should form the lubricating film 715 (it is shown by the dashed-dotted line B in the figure). (Up to the position indicated by the solid line E in the figure), the lubricating film 715 is formed. Thus, durability can be improved by covering surface D with a lubricating film so that the acid of a roughness may not be exposed, respectively. The lubricating film 715 is preferably formed continuously in the raceway or the like as shown in FIG. 30, but may be formed in a discontinuous, for example, island shape.

In addition, in this embodiment, the center line average roughness Ra of the raceway surface of the outer ring 712 of the rolling bearing 710, and the raceway surface of the inner ring 711 is 0.02 micrometer or more and 0.2 micrometer or less, The ball 713 The center line average roughness Ra of the raceway is set to 0.002 µm or more and 0.01 µm or less. By setting it as such surface roughness, the quantity of the lubricating film 715 to be formed can be suppressed and an oscillation suppression effect can be improved. The fluorine-based lubricant forming the lubricating film 715 contains PTFE powder and fluorine-based lubricant as a fluorine resin, and is in a so-called gel state.

As the fluorine-based lubricant, for example, a fluoro polyether polymer or a poly fluoro alkyl polymer is used. Examples of the fluoropolyether polymer include those having a number average molecular weight of 1000 to 50000 in a polymer having a unit represented by a general formula (X is an integer of 1 to 4) represented by -C _X F _2X -O- as a main repeating unit. have. In addition, the polyfluoroalkyl polymer is represented by the formula (n is a natural number) of R _1- (CF ₂ ) _n -R ₂ , and examples of R ₁ and R ₂ include those shown in the following formula (13). In addition, R <_1> and R <_2> may be the same and may differ.

(Formula 13)

In addition to the fluorine-based lubricating oil, in addition to having no functional group in the molecular structure, a certain amount of a functional group in the molecular structure may be added. As for this functional group, a thing having high affinity for metal, for example, an epoxy group, an amino group, a carboxyl group, a hydroxyl group, a mercap group, a sulfone group or an ester group, is preferable, and a fluorine-based lubricant having a functional group in its molecular structure As an example, what is shown to following General formula (14), 15 is mentioned.

(Formula 14)

(Formula 15)

As the above-mentioned fluorine-based lubricating oil, in detail, a mixture with purple ore polyether (PFPE) or a derivative thereof, for example, the brand name FONBLIN Y standard of AUGEMONT Co., Ltd., von furin emulsion (FE 20, EM) 04) or von Purin Z derivatives (FONBLIN Z DEAL, FONBLIN Z DIAC, FONBLIN Z DISOC, FONBLIN Z DOL, FONBLIN Z DOL TX2000, FONBLIN Z TETRAOL, etc.) are suitably used.

As the fluororesin, in addition to PTFE, ethylene tetrafluoride perfluorovinyl ether copolymer (PFA), ethylene fluoride propylene copolymer (FEP) and the like can be used.

A mixture of the fluorine lubricant and the PTFE powder is used as the fluorine lubricant. However, since PTFE powder is mixed with the above-mentioned fluorine-type lubricating oil, since all have high density | concentration, it is preferable to use the diluted fluorine-type lubricant dilution solution for an oil plating process with a suitable dilution solvent as mentioned later.

Next, an example of an oil plating process is demonstrated. First, the outer ring 712, the inner ring 711, the ball 713, and the retainer 714 are assembled to bring the rolling bearing 710 to a completed state, and then the outer ring 712 and the inner ring 711 after degreasing and cleaning. ), The prepared fluorine-based lubricant dilution solution is injected into the location where the ball 713 is present by the eyedropper as necessary. Thereafter, the rolling bearing 710 is rotated several times to attach the fluorine-based lubricant dilution solution to the outer race 712, the inner race 711, the ball 713, and the transmission portion and the slide portion of the retainer 714. Supply of this fluorine-type lubricant dilution solution may be performed by application | coating, and may be performed by spraying using a spray. Alternatively, the rolling bearing 710 assembled in the storage tank of the fluorine-based lubricant dilution solution may be pulled up after being immersed to supply the fluorine-based lubricant dilution solution.

Here, the prepared fluorine lubricant is composed of, for example, 90% by mass of von Purine Z 25 (fluorinated lubricant having no functional group in its molecular structure) and 10% by mass of von Purine Z DOL (fluorinated lubricant having functional groups in its molecular structure). Will be. In addition, the attached fluorine-based lubricant dilution solution adjusts the fluorine-based lubricant formed by mixing 80% by mass of this fluorine-based lubricant and 20% by mass of PTFE powder having a particle diameter of 1 μm or less, and dilute solvent Asahicurin AK until this is 1% by mass. It was obtained by diluting with -225 (made by Asahi Glass Co., Ltd.).

Thereafter, the entire rolling bearing 710 to which the fluorine-based lubricant dilution solution is attached is heated at 120 to 140 ° C. for about 30 minutes to remove the diluting solvent contained in the attached fluorine-based lubricant dilution solution. In this way, a lubricating film made of a fluorine-based lubricant can be formed. Here, the embodiment described above will be described as having performed an oscillation amount test, an out gas velocity test, and a torque endurance test. For comparative examples in the oscillation amount test, the out gas velocity test, and the torque endurance test, a fluorine-based lubricant may be used only from a fluorine-based lubricant having a functional group in a molecular structure, specifically, a fluorine-containing polymer (FONBLIN Z DIAC) having a carboxyl group at its terminal. It was constructed and used. Other conditions, such as a dilution solvent, the oil plating process, and the structure of a rolling bearing, are as above-mentioned. In addition, the dilution concentration of the fluorine-type lubricant dilution solution used for the oil plating process of both the Example and the comparative example was 1%.

In addition, a test bearing is the no. 608 of Seiko Kogyo Co., Ltd. product. Furthermore, the surface roughness Ra of the raceway surfaces of the inner ring and the outer ring is set to 0.05 μm, and the surface roughness Ra of the ball is set to 0.005 μm, respectively, and the lubricating film is formed by the oil plating process as described above. It is.

First, the oscillation amount test will be described. 31A shows a bearing rotation tester (manufactured by Seiko Co., Ltd.) used when performing the oscillation amount test. The inner ring 750a of the test bearing 750 is attached to the spin stone shaft 751 (manufactured by SUS 440C) of the bearing rotation tester. At this time, the axial load on the test bearing 750 is adjustable by the spring 755.

A magnetic fluid seal unit 756 is installed at one end of the spindle shaft 751, and rotational torque of the motor 754 is applied to the spindle shaft 751 by the pulley 757, the belt 758, the pulley 759, And a magnetic fluid seal unit 756. On the other hand, the outer ring 750b of the test bearing 750 is connected to the micro load transducer 760 via the housing 752, and therefore, the torque of the test bearing 750 is adjusted using the micro load transducer 760. I can measure it.

The test bearing 750 is surrounded by the container 761 and the partition wall 762, and the bottom of the space is connected to the laser light scattering particle counter 763. On the other hand, the air inlet 765 is provided in the upper part of this enclosed space through the filter 764. The air inlet 765 supplies clean air to a space surrounded by the container 761 and the partition wall 762 at a predetermined flow rate, and air flow is generated from the air inlet 765 toward the particle counter 763. Therefore, the amount of wear and tear generated in the test bearing 750 can be detected by the particle counter 763.

As a result of performing the oscillation amount test under the test conditions that the rotational speed of the test bearing 750 is 1000 rpm and the load is 50 N, as shown in FIG. 31B, the present embodiment oscillates as compared with the comparative example. amount (dog / m ³⁾ was a very low level to 1/10 or less. Next, out gas velocity test (Throughput method) is demonstrated. 32 (a), the outgas velocity evaluation test apparatus used for this test is shown.

In the out-gas velocity evaluation test apparatus, the sample chamber 792 in which the test bearing 790 is accommodated, and the analysis chamber 791 to which the turbomolecular pump 796 and the rotary pump 797 are connected, have a diameter (R). It is connected by the hole 793 which has a circular cross section of 2-3 mm. When the gas in the analysis chamber 791 is sucked by the turbo molecular pump 796 and the rotary pump 797, the air pressure in the analysis chamber 791 is lower than that in the sample chamber 792. Gas flows into the analysis chamber 791 through the hole 793. In addition, a quadrupole mass spectrometer 798 is also provided in the analysis chamber 791 in the figure, and the type of gas generated in the sample chamber 792 and introduced into the analysis chamber 791 can be analyzed.

In a state where gas flows from the sample chamber 792 to the analysis chamber 791, the air pressure is measured by ion gauges 794 and 795 provided in the sample chamber 792 and the analysis chamber 791, respectively, and the test bearing ( The outgas generation rate (out gas velocity) at 790 is measured. Out gas velocity can be calculated | required by following formula (1).

Qb = C (P ₂ -P ₁ ) -Qc... (One)

Here, each value in Formula (1) is as follows.

Qb: Out-gas velocity of test bearing (Pam ³ / s)

Qc: Out gas velocity of the chamber (Pam ³ / s)

C: Conductance of the hole (integer) (m ³ / s)

P ₁ : Analysis chamber chamber pressure (Pa)

P ₂ : Sample chamber chamber pressure (Pa)

In addition, the out-gas velocity Qc of the said chamber is the out-gas velocity measured when the test bearing 790 is not accommodated in the sample chamber 792, and can be calculated | required by following formula (2) based on the measurement value of atmospheric pressure. will be.

Qc = C (P ' ₂ -P' ₁ ). (2)

Here, P ' ₁ and P' ₂ are the analysis chamber chamber pressure and the sample chamber chamber pressure measured when the test bearing 790 is not received, respectively.

Moreover, about the result of the outgas velocity test, as shown to FIG. 32 (b), it turned out that the thing of this embodiment is significantly lowered by about 1/5 compared with the comparative example. In addition, the outgas velocity shown in FIG. 32 is shown by the relative value when the outgas velocity of a comparative example is set to one.

Moreover, the torque endurance test is demonstrated. In the torque endurance test, a bearing rotation tester (manufactured by Seiko Kogyo Co., Ltd.) shown in Fig. 31A was used in the same manner as the oscillation amount test. The test bearing 750 was driven at a rotational speed of 1000 rpm and a load of 50 N, and the torque of the test bearing 750 after a predetermined time elapsed was measured using the micro load transducer 760. As for the result of this torque endurance test (in air | atmosphere), as shown in FIG. 33, although the torque value became remarkably high in the vicinity of more than 100 hours from the test start of the comparative example, the thing of this embodiment is 500 hours. Even if it fell, it was able to continue almost without change with the low torque value.

In addition, this invention is not limited only to embodiment mentioned above, A various application and a deformation | transformation are conceivable. For example, in the present embodiment, the present invention is applied to a deep groove ball bearing, but the present invention can also be applied to rolling bearings of other bearing types. In addition to rolling bearings, the present invention can be similarly applied to linear bearings such as linear guide devices and linear bearings shown in FIGS. 34 and 35, ball screw devices and the like shown in FIG. 36.

34 is a front view showing the linear guide device 720 (the transmission device) with the end cap omitted. Linear guide device 720 (product number: LS 20 AL, Japan Seiko Co., Ltd.) is a square guide rail 721 having a rolling element rolling groove 721a having a circular arc cross section in the axial direction on both sides thereof. The inner side) and the guide rail 721 are provided with the slider 722 (outer side member) of the substantially co-shaped cross-sectional shape which is moved so that relative movement to an axial direction is possible.

Both inner side surfaces of the slider 722 are provided with a rolling element rolling groove 722a having an arc shape in cross section facing the rolling element rolling groove 721a of the guide rail 721, and the front of the guide rail 721 is provided. A plurality of balls 723 (only a part of which is shown as a rolling element) are formed in a linear ball transmission space in which the cross section formed by the body rolling groove 721a and the rolling member rolling groove 722a of the slider 722 is substantially circular. It is loaded so as to be electrically powered.

The contact surface of the rolling element rolling groove 721a and the ball 723 of the guide rail 721 of the linear guide device 720 and the contact surface of the rolling element rolling groove 722a of the slider 722 with the ball 723. Is equivalent to the raceway surface of the inner and outer rings of the rolling bearing 710 of the above embodiment, and the ball 723 of the linear guide device 720 is the ball of the rolling bearing 710 of the above embodiment. It corresponds to (713). Therefore, the surface roughness of each of the rolling elements rolling grooves 721a and 722a and the ball 723 is set in the same manner as in the above embodiment, and similar lubricating films (not shown) are formed in accordance with the above-described method, respectively. . Therefore, the linear guide device 720 has little oscillation and outgas, and is excellent in durability.

In addition, the linear bearing 730 shown in FIG. 35 has the outer cylinder 732 (outer member) arrange | positioned outside the shaft 731 (inner side member), the shaft 731, and the outer peripheral surface 731a of the shaft 731, and outer cylinder. A plurality of balls 733 are mounted so as to be rotatably loaded between the inner diameter surface 732a of the 732, and the shaft 731 or the outer cylinder 732 is moved according to the rolling of the balls 733. It is a structure which moves relatively to an axial direction. Moreover, the fitting 734 is for preventing the movement | movement more than a fixed distance by the rolling of the ball 733.

The outer circumferential surface 731a of the shaft 731 of the linear bearing 730 and the inner diameter surface 732a of the outer cylinder 732 correspond to the raceway surface of the inner and outer rings of the rolling bearing 710 of the said embodiment, The ball 733 in the linear bearing 730 corresponds to the ball 713 in the rolling bearing 710 of the said embodiment. Accordingly, the outer circumferential surface 731a, the inner diameter surface 732a, and the ball 733 have surface roughnesses set in the same manner as in the above-described embodiments, and similar lubricating films (not shown) are obtained in accordance with the above-described method. Formed. Therefore, the linear bearing 730 has little oscillation and outgas, and is excellent in durability.

The ball screw device 740 shown in FIG. 36 includes a screw shaft 741 (inner member) having a spiral track groove on its outer circumference and a nut 742 (outer member) having a spiral track groove on its inner circumference; And a plurality of balls 743 (rolling elements) mounted between the two tracks so as to be rotatable, and the screw shaft 741 or the nut 742 are rotated by either of the screw shafts 741. One side linearly moves relative to an axial direction. In addition, the ball 743 is electrically driven between the raceway groove 741a of the screw shaft 741 and the raceway groove 742b of the nut 742, and then the circulator tube 744 attached to the nut 742 is provided. It is in the form of circulation through.

The surface of the raceway groove of the screw shaft 741 and the raceway groove of the nut 742 in this ball screw device 740 has the inner and outer rings 711 and 712 in the rolling bearing 710 of the said embodiment. ), And the ball 743 in the ball screw device 740 corresponds to the ball 713 in the rolling bearing 710 of the above embodiment. Accordingly, the track grooves of the screw shaft 741, the track grooves of the nut 742, and the balls 743 have surface roughnesses set in the same manner as in the above-described embodiments, and the same lubricating film as described above. (Not shown) are formed respectively. Therefore, the ball screw device 740 has little oscillation and outgas, and is excellent in durability.

(B of the fifth embodiment)

The difference from A of the fifth embodiment is that a hydrocarbon-based lubricant is used in place of the fluorine-based lubricant as the lubricant constituting the lubricating film in the present invention. Hereinafter, it demonstrates centering on the oil plating process of this hydrocarbon type lubricating oil and the lubricant containing the said lubricating oil.

FIG. 37 is a cross-sectional view of a part of the ball 773 serving as a rolling element of the rolling bearing 770 (the transmission device) subjected to the oil plating process using a lubricant containing a hydrocarbon-based lubricant and a fluorine resin. The rolling bearing 770 of B of 5th Embodiment has the structure substantially the same as the rolling bearing 710 shown in FIG. 29, and is only in the attachment state of the constituent material of the lubricating film 775, and the lubricating film 775. FIG. It makes a difference. Reference numeral 771 denotes an inner ring, 772 an outer ring, 773 a ball, and 774 a retainer.

FIG. 38 is an enlarged schematic diagram showing the formation state of the lubricating film 775 on the raceway surface of the outer ring 772, the raceway surface of the inner ring 771, or the raceway surface of the ball 773. FIG. The raceway surface of 772 (inner ring 771) and the raceway surface of the ball 773 are shown by the figure (b).

As shown in the figure, in this embodiment, the lubrication film 775 is formed to a position approximately equal to the calculation line of the roughness on the surface on which the lubrication film 775 is to be formed. In order to improve durability, as in A of the fifth embodiment, it is preferable to cover the raceway surface with a lubricating film to a degree that exceeds the roughness calculation line. good. In this case, since the amount of the lubricating film is small, there are less oscillation and out gas. In addition, although the lubricating film 775 is formed continuously in track surface etc. in the same figure, it may be formed in discontinuous, for example, island shape.

Moreover, the centerline average roughness Ra of the track surface of the outer ring 772 of the rolling bearing 770 and the track surface of the inner ring 771 of this embodiment is 0.02 micrometer or more and 0.2 micrometer or less, More preferably, it is 0.02 μm or more and 0.08 μm or less. The center line average roughness Ra of the raceway surface of the ball 713 is 0.002 micrometer or more and 0.01 micrometer or less, More preferably, it is 0.002 micrometer or more and 0.005 micrometer or less.

The lubricant forming the lubricating film 775 contains a lubricating oil containing fluororesin powder and alkylated cyclopentane or polyphenyl ether as main components, and is in a so-called gel state.

Examples of such alkylated cyclopentane include tri (2-octyldodecyl) cyclopentane. Moreover, as tri (2-octyldodecyl) cyclopentane, the Synthetic Oil 2001A (brand name) by NyeLubicants company is marketed, for example. Further, tri-n-octyl cyclopentane, tetra-n-octylcyclopentane, penta-n-octyl cyclopentane, tri-n-nonyl cyclopentane, penta n-nonylcyclopentane, penta-n-decyl cyclopentane, penta Alkylated cyclopentane, such as -n-dodecyl cyclopentane, tetra-2-ethylhexyl cyclopentane, etc., has a vapor pressure of 20 占 폚 at 1 × 10 ⁻⁵ Pa or less (for example, 1 × 10 ⁻⁷ to 1 × 10 ⁻ Since it is low as ⁸ Pa), it can use as lubricating oil. When such alkylated cyclopentane is used, the lubricant is hardly evaporated even when the transmission device of the present invention is used in a vacuum.

As the polyphenyl ether, for example, phenyl ether type synthetic oil of Matsumura Petroleum Research Institute can be used, and among these, pentaphenyl ether, tetra phenyl ether, mono alkyl tetra phenyl ether, dialkyl tetra phenyl ether, mono alkyl triphenyl Ether and alkyl diphenyl ether can be used suitably. Such polyphenyl ether has a low vapor pressure and excellent heat resistance, so there is little outgas even in a vacuum or a high temperature environment.

Next, an example of the oil plating process of the lubricant of this embodiment is demonstrated. First, the outer ring 772, the inner ring 771, the ball 773, and the retainer 774 are assembled to bring the rolling bearing 770 to a completed state, and then the outer ring 772 and the inner ring 771 after degreasing cleaning. ), Only a necessary amount is injected into the location where the ball 773 exists between the dilution solution of the prepared lubricant by a dropper or the like. Thereafter, the rolling bearing 770 is rotated several times, so that the dilution solution is attached to the outer ring 772, the inner ring 771, the ball 773, and the transmission site of the holder 774 and the slide site. Supply of this diluent may be performed by application | coating, and may be performed by spraying using a spray. Alternatively, the dilution solution may be supplied by pulling up the rolling bearing 770 assembled in the storage tank of the dilution solution after dipping.

The lubricant prepared here consists of 60 mass% of Synthetic Oil 2001A (brand name) by NyeLubicants, and 40 mass% of PTFE powder with a particle diameter of 1 micrometer or less, for example. The dilution solution of this lubricant is obtained by diluting the lubricant with a dilution solvent such as hexane or AsahiClean AK-225 (manufactured by Asahi Glass Co., Ltd.) until it reaches 1% by mass. As the fluorine resin, dry film RA / I PA manufactured by DuPont Co., Ltd., in which PTFE was dispersed in a solvent, was used.

Thereafter, the entire rolling bearing 770 to which the dilution solution is attached is heated at 100 to 140 ° C. for about 30 minutes to remove the dilution solvent contained in the adhered dilution solution. In this way, a lubricating film made of the lubricant of the present embodiment can be formed.

Here, the B of the fifth embodiment described above is described as having performed the oscillation amount test and the torque endurance test. For the comparative examples in the oscillation amount test and the torque endurance test, the lubricant was composed of and used only with a fluorine-based lubricant having a functional group in the molecular structure, specifically, a fluorine-containing polymer (FONBLIN Z DIAC) having a carboxyl group at the terminal. The other conditions, such as the kind of dilution solvent, the oil plating process, and the structure of a rolling bearing, are the same as that mentioned above in B of 5th Embodiment. In addition, the dilution concentration of the dilution solution used for the oil plating process of both the Example and the comparative example was 1%.

In addition, the test bearing is No. 608 (inner diameter 8mm, outer diameter 22mm, width 7mm) by Seiko Co., Ltd., Japan. Furthermore, the surface roughness Ra of the raceway surface of the inner ring and the outer ring is 0.05 μm, and the surface roughness Ra of the ball is set to 0.005 μm, respectively, and the respective surfaces are subjected to the oil plating treatment as described above. And a lubricating film is formed. The oscillation amount test for the test bearing is a fifth embodiment using a tester such as a bearing rotation tester (see FIG. 31 (a)) used for the oscillation amount test in A of the fifth embodiment. It carried out by the method similar to the oscillation amount test in A. In addition, the test conditions are the same, and the rotational speed of the test bearing 750 is 1000 rpm and the load is 50N.

The test results are shown in the graph of FIG. As shown in the figure, the amount of oscillation (pieces / m ³ ) of the present embodiment was extremely low at 1/10 or less as compared with that of the comparative example.

Next, a torque endurance test performed on the test bearing will be described. Also in this torque endurance test, similarly to the said oscillation amount test, using the bearing rotation test machine shown to Fig.31 (a), the test bearing 750 is driven with a rotational speed of 1000 rpm and a load of 50N, and for predetermined time. The torque of the test bearing 750 after elapsed was measured using the micro load transducer 760. The test results are shown in the graph of FIG.

As shown in the figure, the torque value of the comparative example was significantly increased near 100 hours after the start of the test, but the embodiment of the present embodiment could continue almost unchanged with a low torque value even after 500 hours. there was.

In addition, this invention is not limited only to B of 5th Embodiment mentioned above, A various application and a deformation | transformation are conceivable. For example, as described in A of the fifth embodiment, the linear guide device shown in Figs. 34 and 35, in addition to the rolling bearing of a bearing type other than the deep groove ball bearing, and the rolling bearing, The present invention can be similarly applied to linear bearings such as linear bearings and the ball screw device shown in FIG.

(6th embodiment)

This embodiment relates to rolling support devices, such as a rolling bearing, a ball screw, a linear guide, and a vacuum conveying apparatus. In addition, the inorganic hard film in this embodiment is suitable also as a base of lubricating films, such as the DFO lubricating film of 1st-5th embodiment mentioned above.

Examples of applications of the linear guide include a device used in a vacuum state such as a sputtering device, a plasma CVD device, an ion implantation device, etc., which are part of a facility for manufacturing a liquid crystal display panel, a semiconductor device, a solar cell panel, a hard disk device, or the like; The apparatus etc. which are used in a clean environment are mentioned. In the linear guide for such a use, as the guide rail and the slider, those formed of stainless steel (mainly SUS 440C) and having been quenched and tempered on the surface are used. Fluorine-based lubricants are used as lubricants.

By the way, it is known that the product performance of a liquid crystal display panel, a semiconductor device, a solar cell panel, a hard disk device, etc. is impaired by adhering fine particle (foreign material) to the surface. In recent years, miniaturization and integration of such a device progress, and it is required to manufacture in the environment with higher cleanliness in order to improve product yield. Moreover, in order to improve the productivity of a product, as the speed | rate of the linear guide used for a conveying apparatus advances, the problem of the fine particle which has not been a problem so far becomes remarkable. Furthermore, in order to reduce the product cost in addition to improving the product yield, durability of the linear guides used in these devices is required as the maintenance free of the device itself and the prolongation of the maintenance cycle are required.

In order to solve such a problem, Japanese Patent Laid-Open No. 2003 314572 discloses that a hard film made of a metal compound or the like is formed on at least one of the inner raceway surface, the outer raceway surface, and the rolling element rolling surface of a bearing for a rotary introducer, By coating this hard film with the lubricating film containing a fluorine-containing polymer and a PFPE which have a functional group, it is proposed to give a bearing low oscillation property, lubricity, and durability.

However, in the bearing described in the above-mentioned publication, the adhesion between the hard film and the lubricating film is not mentioned. When the lubricating film is peeled off from the hard film, low dusting property, lubricity and durability deteriorate. For this reason, there is room for improvement in that the bearing described in the above-mentioned publication is suitably used in a vacuum environment or a clean environment.

Then, this invention improves the adhesiveness of a hard film and a lubricating film, and makes it a 1st subject to provide the rolling support apparatus which can be used suitably also in a vacuum environment or a clean environment. Moreover, this invention makes it a 2nd subject to make it possible to reduce oscillation, and to improve lubricity and durability in the vacuum conveying apparatus used in a vacuum environment.

MEANS TO SOLVE THE PROBLEM In order to solve such a subject, this invention is equipped with the 1st member and 2nd member provided with the track surface mutually arrange | positioned, and the 3rd member arrange | positioned between the said 1st member and the 2nd member, In the rolling support device in which one of the first member and the second member is relatively moved relative to the other as the third member is driven or slides, at least one of both raceway surfaces of the first member and the second member is made of metal. An inorganic hard film is formed on the raceway surface by thermal spraying, and the inorganic hard film is coated with a lubricating film, and the porosity of the inorganic hard film is 0.5 vol% or more and 10.0 vol% or less. It provides a rolling support device characterized in that.

According to this, since the pores which exist in an inorganic hard film | membrane act as a lubricant storage and an anchor (reinforcement material), the adhesiveness of an inorganic hard film | membrane and a lubricous film improves. Here, when the porosity of the inorganic hard membrane is less than 0.5% by volume, the pores present in the inorganic hard membrane cannot effectively act as a lubricant storage and anchor, and when the porosity exceeds 10.0% by volume, the inorganic hard membrane itself becomes easily peeled off. . The porosity of the inorganic hard membrane is preferably in a range of 1.0% by volume to 8.0% by volume, and more preferably in a range of 3.0% by volume to 5.0% by volume.

Moreover, as a kind of thermal spraying, a plasma spraying method, a gas spraying method, an arc spraying method, a frame spraying method, an ultrasonic frame spraying method, an explosion spraying method, a reduced pressure plasma spraying method, etc. are mentioned. Examples of the thermal spraying materials include gray alumina, white alumina, titanium dioxide, chromia, alumina titanium dioxide, spinel, mourite, zirconia-ytria, zirconia-magnesia, zirconia-carcia, zirconia-murite, zirconia-silica, And fine particles such as cobalt blue. Other thermal spray materials include vanadium-carbide, chromium carbide, tungsten carbide, tungsten carbide cobalt chromium, tungsten carbide cobalt, boron carbide, zirconium carbide, titanium boride, molybdenum boride, zirconium boride, titanium carbide Nickel, titanium nitride, zirconium nitride, silicon carbide, silicon nitride, or the like may be used alone or in combination.

Here, the inorganic hard film formed by the thermal spraying may have a rough surface, and the surface may act as an abrasive (abrasive material) to wear the mating member. For this reason, after forming an inorganic hard film | membrane by spraying, it is preferable to perform mechanical processing, such as grinding | polishing, and to make the surface roughness of an inorganic hard film | membrane below a predetermined value. For example, when the rolling support device is a rolling bearing, a linear guide, a ball screw, a linear bush, or the like, it is preferable that the surface roughness Ra of the inorganic hard film formed on at least one of the two raceway surfaces is 0.2 μm or less. .

Moreover, as a kind of metal which forms at least one of the both track surfaces of the said 1st member and the 2nd member, "SUS 440C", "steel material whose alloy component is C: 0.65 mass% and Cr: 13 mass%", and Martensitic stainless steels such as `` steel alloys having a C: 0.45% by mass, Cr: 13% by mass and N: 0.14% by mass '', and austenitic stainless steels such as SUS 304 and SUS 316. Precipitation hardening stainless steel, such as "SUS 630", etc. are mentioned. Moreover, after processing the raw material which consists of such steel to a predetermined shape, it is preferable to perform a hardening heat treatment or a diffusion process, and to harden a surface.

In the rolling support apparatus of this invention, it is preferable that the said inorganic hard film consists of at least one of a cemented carbide, a cermet, and ceramics. Moreover, in the rolling support device of this invention, it is preferable that the thickness of the said inorganic hard film is 0.05 mm or more and 1 mm or less. If the thickness of the inorganic hard film is less than 0.05 mm, wear resistance cannot be imparted to the rolling support device. On the other hand, when the thickness of the inorganic hard film exceeds 1 mm, the inorganic hard film may break due to the internal stress of the inorganic hard film itself, and the film forming cost increases. The preferred range of the thickness of the inorganic hard film is 0.1 mm or more and 0.5 mm or less.

Moreover, in the rolling support device of this invention, it is preferable that the said lubricating film consists of lubricating oil whose vapor pressure in 25 degreeC is 1 * 10 <^-5> Pa or less. Examples of such lubricating oils include fluorine oil, polyphenyl ether oil, alkylated cyclopentane, shirahydrocarbon oil, and ester oil. According to this, even if a rolling support device is used in a vacuum environment, since the lubricating oil which comprises a lubricating film does not vaporize, a lubricating film is protected and hold | maintained on the upper surface of an inorganic hard film for a long time.

In addition, examples of the fluorine oil that can be used in the present invention include fluoro polyether, polyfluoroalkyl, and those having a functional group in these. Examples of the fluoropolyethers include those having a number average molecular weight of 1000 to 50000 in polymers having units represented by the general formula (X being an integer of 1 to 4) represented by -C _X F _2X -0- as the main repeating unit.

Moreover, as polyfluoroalkyl, what is shown by following formula (16) is mentioned. Y shown by General formula (16) is a functional group with high affinity with respect to a metal, For example, an epoxy group, an amino group, a carboxyl group, a hydroxyl group, a mercap group, a sulfone group, an ester group, etc. are preferable. As polyfluoroalkyl, what is shown to following formula (17) and formula (18) besides what is shown by General formula (16) is mentioned.

(Formula 16)

(Formula 17)

Formula 18

As a specific example of the fluorine oil which has the above-mentioned functional group, the brand name Klitox 157 FSL, 157 FSM, 157 FSH of the DuPont company, and the brand name Gemnam modified product SA, SH, SY-3, SP of the Daikin Industries Co., Ltd., Montecatini company The product name includes von Purin Z-DEAL, Z-DIAC, Z-DISCO, Z-DOL, Z-DOLTX2000, and the like.

Moreover, as a specific example of the perfluoro polyether (PFPE) which is a kind of fluoro polyether, the brand name S-200, S-100, S-65 of the Daikin Industries company, and the brand name von purine Z-25 of Montecachina company make , Z-60, 40/11, and the trade name Klytox 16140 manufactured by DuPont. Examples of the polyphenyl ether oil that can be used in the present invention include pentaphenyl ether, tetraphenyl ether, mono alkyl tetraphenyl ether, dialkyltetra phenyl ether, monoalkyl triphenyl ether, alkyl diphenyl ether and the like, manufactured by Matsumura Petroleum Institute Co., Ltd. Can be mentioned. Since these polyphenyl ether oils are low in vapor pressure and have excellent heat resistance, they can be suitably used even in a vacuum environment or a high temperature environment.

Examples of the alkylated cyclopentane that can be used in the present invention include tri (2-octyldodecyl) cyclopentane and the like. As a specific example of this tri (2-octyldodecyl) cyclopentane, the brand name Synthetic Oil 2001A by NyeLubicants company is mentioned. In addition, as another example of the alkylated cyclopentane, tri-n-octylcyclopentane, tetra-n-octylcyclopentane, penta-n-octylcyclopentane, tri-n-nonyl cyclopentane, penta-n-nonyl cyclopentane, penta -n-decylcyclopentane, penta-n-dodecyl cyclopentane, tetra-2-ethylhexyl cyclopentane, etc. are mentioned. Since these alkylated cyclopentanes have low vapor pressure, they can be used suitably even in a vacuum environment.

Examples of the shirahydrocarbon oil that can be used in the present invention include polymers in which a general formula is a main repeating unit of a unit represented by the following general formula (19). R <_1> -R <_{3> shown} by General formula (19) is a hydrocarbon group of the same kind or different types, and n represents the integer of 0-2. As a specific example of shirahydrocarbon oil, what is shown by following General formula (20) is mentioned.

(Formula 19)

(Formula 20)

As ester oil which can be used by this invention, the brand name NyeTorr 5101 by Nye Lubicants company, etc. are mentioned.

Moreover, in the rolling support device of this invention, it is preferable that the said lubricating oil contains the particle | grains (particle diameter 0.3-5 micrometers) which consist of a fluororesin. According to this, since the particle | grains which consist of a fluororesin trap the extra lubricating oil which becomes a cause of oscillation, oscillation from a rolling support apparatus reduces. Examples of the fluorine resin that can be used in the present invention include polytetrafluoroethylene (PTPE), ethylene tetrafluoride perfluorovinyl ether copolymer (PFA), and ethylene fluoride propylene copolymer (FEP).

Here, as a method of forming a lubricating film, for example, after diluting or mixing fluorine oil with a fluorine-based solvent to a predetermined concentration, a method of immersing and pulling up a member for providing a lubricating film in a solution to which PTFE powder is added is mentioned. Can be. Moreover, the method of operating a rolling support apparatus after the predetermined amount of the said solution is inject | poured in a rolling support apparatus is also mentioned. In addition, the thickness of a lubricating film can be arbitrarily controlled by setting of the density | concentration of a solution, the injection amount, etc. In addition, after forming a lubricating film, in order to remove a volatile component, it is preferable to perform vacuum drying.

Moreover, in the rolling support device of this invention, it is preferable that the thickness of the said lubricating film is 0.1 micrometer or more and 100 micrometers or less. If the thickness of this lubricating film is less than 0.1 µm, the lubricating effect cannot be obtained. On the other hand, when the thickness of the lubricating film exceeds 10 µm, the torque increases or oscillation increases due to the resistance of the lubricating film. The range of the thickness of a lubricating film is 0.2 micrometer or more and 5 micrometers or less.

The present invention also provides a vacuum conveying unit comprising a conveying unit provided with a guided surface, a conveying roller for guiding the conveying unit by sliding the guided surface, and a rolling bearing slidably supporting the conveying roller with respect to the guided surface. In the apparatus, at least one of the guide surface and the slide surface of the conveying roller that slides thereon is formed of a metal, and an inorganic hard film is formed on the guide surface and the slide surface by thermal spraying, and the inorganic hard film is coated with a lubricating film. The porosity of the inorganic hard membrane is 0.5% by volume or more and 10.0% by volume or less, and the raceway surface of the rolling bearing is covered with the lubricating film. .

In the vacuum conveying device, the inorganic hard film formed on at least one of the guide surface and the slide surface of the conveying roller is at least one of cemented carbide, cermet, and ceramics, similar to the inorganic hard film used in the above-described rolling support device. It is preferable to form and to make the thickness into 0.05 mm or more and 1 mm or less. The surface roughness Ra of the inorganic hard film is preferably 1.6 µm or less, more preferably 0.8 µm or less, and still more preferably 0.4 µm or less.

In addition, the lubricating film covering the inorganic hard film formed on at least one of the guide surface and the slide surface of the conveying roller has a vapor pressure of 1 × 10 ^-5 Pa at 25 ° C. similarly to the lubricating film used in the above-described rolling support device. It is preferable to form with the following lubricating oil, and to make the thickness into 0.1 micrometer or more and 10 micrometers or less. At this time, the lubricating oil is preferably at least one of fluorine oil, polyphenyl ether oil, alkylated cyclopentane, sirahydro carbon oil, and ester oil, similarly to the lubricating oil used in the above-mentioned rolling support device, It is more preferable to include.

In addition, in this invention, a "cloud support apparatus" refers to a rolling bearing, a ball screw, an electric linear guide, a sliding linear guide, a linear bush, etc. Here, when a rolling support device is a rolling bearing, a 1st member and a 2nd member refer to an inner ring and an outer ring, and a 3rd member points to a rolling element. In addition, when a rolling support device is a ball screw, a 1st member and a 2nd member point to a screw shaft and a nut, and a 3rd member points to a rolling element. Furthermore, when the rolling support device is an electric linear guide, the first member and the second member point to the guide rail and the slider, and the third member point to the rolling element. Furthermore, when the rolling support device is a slide linear guide, the first member and the second member point to the guide rail and the slider, and the third member point to the slide body. Moreover, when the rolling support device is a linear bush, the first member and the second member point to the raceway shaft and the outer cylinder, and the third member point to the rolling element.

According to the rolling support device of the present invention, an inorganic hard film whose porosity is specified by thermal spraying is formed on at least one of both raceway surfaces of the first member and the second member, and the inorganic hard film is further covered with a lubricating film. This improves the adhesion between the inorganic hard film and the lubricating film. Therefore, the rolling support device of the present invention can be suitably used even in a vacuum environment or a clean environment because oscillation is reduced and lubricity and durability are improved.

In addition, according to the vacuum conveying apparatus of the present invention, an inorganic hard film having a porosity specified by thermal spraying is formed on at least one of the guide surface provided on the conveying section and the slide surface of the conveying roller that slides thereon. By coating with a lubricating film, the adhesiveness of an inorganic hard film and a lubricating film improves. Therefore, the vacuum conveyance apparatus of this invention reduces oscillation and improves lubricity and durability.

Hereinafter, a sixth embodiment will be described with reference to the drawings.

(A of the sixth embodiment)

It is a figure which shows the linear guide which is an example of the rolling support apparatus of this invention. As shown in FIG. 41, the linear guide 810 includes a guide rail 811 (first member), a slider 812 (second member), and a plurality of balls 813 (third member). The plurality of balls 813 are electrically driven between the track grooves 811a (track surface) formed in the guide rail 811 and the track grooves 812a (track surface) formed in the slider 812. The slider 812 is configured to linearly move along the guide rail 811.

In this embodiment, the guide rail 811 and the slider 812 were first processed into a predetermined shape of a material made of SUS 440C, and then produced by quenching and tempering. Next, a hard film made of WC-12% Co alloy is formed in both the track groove 811a (track surface) formed in the guide rail 811 and the track groove 812a (track surface) formed in the slider 812. Inorganic hard film) was formed by high-speed frame spraying so that the porosity was 1 to 8% by volume and the thickness was 0.15 mm.

Next, the surface roughness Ra of the hard film was 0.1 μm by polishing. Next, a lubricating film made of fluorine oil containing 10% of PTFE having a particle diameter of 0.3 to 5 µm was formed by the immersion method so as to cover the hard membrane so as to have a thickness of 1 µm. And the linear guide was assembled using the guide rail 811 obtained in this way, the slider 812, and the ball 813 made of silicon nitride. In addition, although the electric linear guide was demonstrated as a rolling support apparatus in this embodiment, as shown in FIG. 42, the track surface 821a and the slider 822 formed in the guide rail 821 and the 1st member are shown. And the slide member 823 (the third member) are disposed between the raceway surface 822a formed on the second member).

In addition, as shown in FIG. 43, the present invention provides a raceway groove 831a formed on the screw shaft 831 (first member) and a raceway groove 832a formed on the nut 832, the second member. The ball 833 (the 3rd member) is arrange | positioned between the surface), and may be applied to the ball screw 830 comprised so that the nut 832 may linearly move along the screw axis 831. As shown in FIG. Furthermore, as shown in Fig. 44, the present invention provides a track groove 841a (track surface) formed in the track shaft 841 (first member) and a track groove 842a (track surface) formed in the outer cylinder 842 (second member). The ball 843 (the 3rd member) is arrange | positioned between (), and it may apply to the linear bush 840 comprised so that the outer cylinder 842 may linearly move along the track axis 841.

(B of the sixth embodiment)

It is sectional drawing which shows the vacuum conveyance apparatus which is an example of the rolling support apparatus of this invention. This vacuum conveying apparatus is equipped with the conveyance part 850, the conveyance roller 860, the 1st rolling bearing 870, and the 2nd rolling bearing 880, as shown in FIG. . And this vacuum conveyance apparatus forms the film into the board | substrate 850a by conveying the conveyance part 850 in which the board | substrate 850a was set in the direction perpendicular | vertical to the paper surface of FIG. It is configured to perform.

The conveyance part 850 is substantially C-shaped, The conveyance roller arrangement | positioning part 851 in which the conveyance roller 860 is arrange | positioned inside the C-shape, and the recessed part extended on the upper side of C-shape and setting the board | substrate 850a is set. It consists of the board | substrate arrangement | positioning part 852 in which 852a was formed. A groove portion 850A (guided surface) on which the outer circumferential surface 860a of the ring-shaped conveying roller 860 slides is formed on the inner upper portion of the letter C of the conveying roller placing portion 851. Further, C-shaped bottom end surfaces 850B, 850C, and the guide surface of the C-shaped roller conveying unit 851 are guided by the outer ring outer peripheral surface 880A of the second rolling bearing 880.

The first rolling bearing 870 has an inner ring 871, an outer ring 872, and a ball 873. The inner circumferential surface 860B of the conveying roller 860 is fitted to the outer ring outer circumferential surface 870a of the first rolling bearing 870. This 1st rolling bearing 870 supports the conveyance roller 860 so that the outer peripheral surface 860a of the conveyance roller 860 can slide the guide surface 850A. As shown in FIG. 46, the second rolling bearing 880 includes an inner ring 881, an outer ring 882, a ball 883, a holder 884, and a shield plate 885. The outer ring outer peripheral surface 880A of the second rolling bearing 880 functions as a conveying roller for guiding the conveying unit 850.

That is, in this vacuum conveyance apparatus, the outer peripheral surface 860A of the conveyance roller 860 slides 850A of guide surfaces provided in the conveyance part 850, and the guide surface 850B, 850C provided in the conveyance part 850 is carried out. ) Is guided by the outer ring outer circumferential surface 880A of the second rolling bearing 880, and the conveying unit 850 is configured to be conveyed. In the present embodiment, the inner ring 881 of the first rolling bearing 870 and the inner ring 881 of the outer ring 872 and the second rolling bearing 880 are provided by the conveying unit 850 and the conveying roller 860. The outer ring 882 was produced by processing a raw material made of SUS 440C into a predetermined shape and then performing quenching and tempering treatment. Further, the ball 873 of the first rolling bearing 870 and the ball 883 of the second rolling bearing 880 are made of a material made of silicon nitride, and the retainer of the second rolling bearing 880 is obtained. (884) was made of a material made of SUS 304.

Next, the guide surfaces 850A, 850B, and 850C of the conveying section 850, the outer circumferential surface 860A of the conveying roller 860, and the outer ring outer circumferential surface 880A of the second rolling bearing 880 are WC-. A hard film made of a 12% Co alloy was formed by a high-speed frame spraying method so that the porosity was 1 to 8% by volume and the thickness was 0.1 mm, and then the surface roughness Ra of the hard film was adjusted to 1.6 μm or less by polishing. Then, the lubricating film which consists of fluorine oil containing 10% of PTFE powder of 0.3-5 micrometers of particle diameters was formed by the immersion method so that a thickness might be set to 1 micrometer so that a hard film may be coat | covered.

Further, on the inner raceway surface 881a and the outer raceway surface 882a of the second rolling bearing 880, a lubricating film made of fluorine oil containing 10% of PTFE powder was formed by immersion to have a thickness of 1 μm. It was. And the vacuum conveying apparatus was assembled using the conveying part 850, conveying roller 860, the 1st rolling bearing 870, and the 2nd rolling bearing 880 obtained in this way.

Hereinafter, the effect of this invention is verified based on this invention example and a comparative example.

(First embodiment)

First, a guide rail for linear guide LS 15 AL (rail width 15 mm, rail length 400 mm) manufactured by Seiko Kogyo Co., Ltd., and a slider are processed into a predetermined shape of a material made of SUS 440C, and then quenched and tempered. Was produced.

Next, in N0.1-10 shown in Table 1, the hard film and the lubricating film were formed in at least one of both track grooves of a guide rail and a slider. Specifically, first, a hard film made of WC-12% Co alloy was formed in such a raceway groove by a high-speed frame spraying method so as to have a thickness of 0.1 mm (100 μm) within a range of 0.4 to 10.1% by volume. . Thereafter, the surface of the hard film was polished, and the surface roughness Ra was set to 0.2 μm or less. Next, a lubricating film made of fluorine oil or a lubricating film made of fluorine oil containing 10% of PTFE powder having a particle diameter of 1 to 2 µm was formed by the immersion method so as to cover the hard film so as to have a thickness of 1 µm (0.001 mm).

On the other hand, in N0.11 shown in Table 1, a lubricating film made of fluorine oil containing 10% of PTFE powder having a particle diameter of 1 to 2 µm in both the guide rails and the slider's both raceway grooves is immersed in a thickness of 1 µm. Formed. The linear guide was assembled using the guide rail obtained by doing in this way, the slider, and the ball which consists of the raw material shown in Table 1. And it assumed that this linear guide was used in vacuum environment (1 * 10 <^-4> Pa), and the endurance test was done. In this endurance test, the linear motion was performed until damage occurred to any of the track grooves of the guide rail or the slider, and the movement time from the start of the test until the damage occurred was made as the endurance life. This result is shown together in Table 1 by the ratio which made the endurance life of N0.11 one.

No. Configuration of the linear guide  Endurance Test Results (B)  Remarks Guide rail Slider ball Dura Lube Dura Lube Material Material Porosity (vol%) Material PTFE presence Material Porosity (vol%) Material PTFE presence One WC-12% Co 3.0  Fluorine oil U WC-12% Co 3.0 Fluorine oil U Silicon nitride 3.3   Foot honor 2 3.0 U 3.0 U SUS 440C 2.6 3 3.0 U --- --- --- ---  Silicon nitride 2.4 4 --- --- --- --- WC-12% Co 3.0  Fluorine oil U 2.8 5 WC-12% Co 3.0  Fluorine oil radish 3.0 radish 2.8 6 3.0 radish 3.0 radish SUS 440C 2.3 7 3.0 radish --- --- --- --- Silicon nitride 2.0 8 --- --- --- ---  WC-12% Co 3.0   Fluorine oil radish 2.4 9 WC-12% Co  0.4 〓〓  Fluorine oil U  0.4 〓〓 U  Silicon nitride 0.8 Comparative example 10  10.1 〓〓 U  10.1 〓〓 U 0.3 11 --- Fluorine oil U --- --- Fluorine oil U SUS 440C One

As shown in Table 1, N0.1-8 which formed the hard film and the lubricating film of the structure (film-forming method, porosity) of this invention in at least one of both track | orbit grooves of a guide rail and a slider are other than the structure of this invention. In comparison with N0.9 and 10 in which hard films and lubricating films were formed, the endurance life was long.

Among N0.1-8, N0.1 and N0.5, N0.2 and N0.6, N0.3 and N0.7, and N0.4 and N0.8 are all the examples which changed only the kind of lubricating film. From these results, it was found that the embodiment in which the lubricating film A made of fluorine oil containing PTFE powder was formed had a longer durability life than the example in which the lubricating film B made of fluorine oil containing no PTFE powder was formed.

On the other hand, in N0.9 having a hard membrane having a porosity smaller than the range of the present invention, the durability of the hard membrane was short because the pores present in the hard membrane could not effectively act as lubrication storage and anchor. Moreover, No. which formed the hard film with a porosity more than the range of this invention. In 10, since the hard film itself peeled off, the durability life was short. From the above results, it has been found that the hard life and the lubrication film of the configuration of the present invention are formed in at least one of the raceway grooves of the guide rail and the slider, so that even when the linear guide is used in a vacuum environment, the endurance life can be extended. .

(Second embodiment)

First, the cylindrical roller (outer diameter 50mm) and spherical roller (outer diameter 50mm, spherical radius of curvature R = 100mm) of each structure shown in Table 2 are processed into the predetermined shape after the raw material which consists of SUS 440C is quenched. And tempering treatment was performed. Here, the cylindrical roller was made into the structure which assumed the guide surface of the conveyance part for vacuum conveying apparatuses, and the spherical roller was made into the structure which assumed the slide surface of the conveyance roller for vacuum conveying apparatuses.

Next, in N0.21-25 shown in Table 2, the hard film and the lubricating film were formed in at least one of the both outer peripheral surfaces of a cylindrical roller and a spherical roller. Specifically, first, a hard film made of a WC-12% Co alloy was formed on such an outer circumferential surface by a high-speed frame spraying method so as to have a thickness of 0.1 mm (100 µm) within a range of 0.4 to 10.1% by volume. Next, the surface of the hard film was polished, and the surface roughness Ra was set to 1.6 µm in the case of the cylindrical roller and 0.4 µm or less in the case of the spherical roller. Subsequently, a lubricating film made of fluorine oil or a lubricating film made of fluorine oil containing 10% of PTFE powder was formed so as to coat such a hard film by a immersion method so as to have a thickness of 1 μm (0.001 mm).

In this way, the adiabatic deep groove ball bearing # 6201 (outer diameter 28mm, inner diameter 12mm, width 10mm) by the Seiko Co., Ltd. product was assembled to each outer peripheral surface of the obtained cylindrical roller and spherical roller. Here, the inner ring, outer ring, and rolling element of the deep groove ball bearing were all made of a material made of SUS 440C, and the retainer was made of a material made of SUS 304. Further, lubricating films made of fluorine oil were formed on both raceways of the inner ring and the outer ring by a immersion method so as to have a thickness of 0.6 µm.

Next, as shown in FIG. 47, the cylindrical roller A and the spherical roller B were arrange | positioned so that each outer peripheral surface might contact, and the two-cylinder tester was assembled. And the oscillation test was done by rotating the cylindrical roller A and the spherical roller B of each structure on condition of the following. In this oscillation test, the amount of occurrence of particles of 0.2 µm or more was measured with a particle counter, and the time from the start of the test until the amount of particles generation of 0.2 µm or more reached 100 / min was used as the oscillation name. This result is shown together in Table 2 by the ratio which made the oscillation name of N0.26 one.

(Vibration test conditions)

Atmosphere: Vacuum environment (1 × 10 ^-4 Pa)

Temperature: room temperature

Load: lOON

Rotational Speed: (cylindrical roller) 200 min ^-1

(Spherical roller) 190 min ^-1

Slip rate of cylindrical rollers and spherical rollers: 10%

No. Composition of Cylindrical Roller Composition of Spherical Roller Oscillation test result (r)   Remarks Dura Lube Dura Lube Material Porosity (vol%) Material PTFE presence Material Porosity (vol%) Material PTFE presence 21 WC-12% Co 3.0 Fluorine oil U    WC-12% Co 3.0  Fluorine oil U 3.2  Inventive Example 22 3.0 radish 3.0 radish 2.8 23 --- --- 3.0 U 2.2 24 WC-12% Co  0.4 〓〓  Fluorine oil U  0.4 〓〓  Fluorine oil U 1.2   Comparative example 25  10.1 〓〓 U  10.1 〓〓 U 0.2 26 --- --- --- --- --- 〓〓〓 --- --- 〓〓〓 --- One

As shown in Table 2, N0.21-23 which formed the hard film and lubrication film of the structure (film-forming method, porosity) of this invention in at least one of the outer peripheral surfaces of a cylindrical roller and a spherical roller is hard other than the structure of this invention. Compared with N0.24, 25 which formed the film | membrane and the lubricating film | membrane, the oscillation name was long. In addition, from the result of N0.21 and N0.22 which differ only in the kind of lubricating film, N0.21 which formed the lubricating film A which consists of fluorine oil containing PTFE powder is a lubricating film which consists of fluorine oil which does not contain PTFE powder ( It was found that the oscillation name was longer than N0.22 which formed B).

On the other hand, in N0.24 having a hard film having a porosity less than the range of the present invention, since the pores present in the hard film could not effectively act as lubrication storage and anchor, the oscillation name was short. Moreover, No. which formed the hard film with a porosity more than the range of this invention. In 25, since the hard film itself peeled off, the oscillation name was short. In the above result, No. By forming the guide surface of the conveyance part for a vacuum conveying apparatus by the structure similar to the cylindrical roller of 21-23, and forming the slide surface of the conveyance roller for vacuum conveying apparatus by the structure similar to the spherical roller of N0.21-23, It turned out that the oscillation name of a vacuum conveying apparatus can be lengthened.

(Seventh embodiment)

The present invention relates to a rolling bearing and a method of manufacturing the same. Moreover, in 1st-6th embodiment mentioned above, it is related with the washing | cleaning method which is very suitable as a pretreatment performed to the part which forms a lubricating film, such as a DFO lubricating film.

When a hydrocarbon compound or the like evaporates in a component or the like of a semiconductor manufacturing apparatus, the semiconductor wafer is contaminated to lower the product yield. Therefore, a rolling bearing used for a semiconductor manufacturing apparatus or the like is required to have a small amount of volatilization of a hydrocarbon compound or the like. Therefore, in recent years, in order to reduce volatile components, such as a hydrocarbon compound adhering to a rolling bearing, or to clean a bearing surface, washing | cleaning with an organic solvent, plasma washing, etc. are strengthened.

However, in the washing with an organic solvent, it was difficult to remove completely until it entered the fine roughness of the surface among the process oil, antirust oil, etc. which are affixed on the rolling bearing. Moreover, there exists a possibility that the organic solvent used for washing | cleaning may not be removed completely from a rolling bearing.

Therefore, many hydrocarbon compounds, such as a process oil, antirust oil, and an organic solvent, remain on the surface of a rolling bearing, and when used for a semiconductor manufacturing apparatus, it may volatilize from a rolling bearing and contaminate a semiconductor wafer.

Then, this invention solves the problem with the prior art as mentioned above, and makes it a subject to provide the rolling bearing with a small volatilization amount of a volatile component, and the manufacturing method of such rolling bearing.

In order to solve the said subject, this invention consists of the following structures. That is, the rolling bearing of this invention is a rolling bearing provided with the inner ring, the outer ring, and the several rolling element arrange | positioned so that rotation is possible between the said inner ring and the said outer ring, The carbon number of 25 carbon or less attached to the surface The amount of the hydrocarbon compound is 0.5 ng / mm ² or less.

Moreover, the manufacturing method of the rolling bearing of this invention is an inner ring based on manufacture of the rolling bearing which has an inner ring, an outer ring, and the some rolling element arrange | positioned so that rotation is possible between the said inner ring and the said outer ring. And, after completion of the assembly of the bearing parts including the outer ring and the rolling element, the organic solvent, the alkali and the acid are washed with at least one of them, and further, the electric resistivity is washed with pure water of 5 MΩ · cm or more.

MEANS TO SOLVE THE PROBLEM As a result of earnestly researching so that the said subject may be solved, the hydrocarbon compound tends to volatilize as carbon number is small, and it is difficult to volatilize with carbon number, and has a volatile hydrocarbon compound which has a bad influence on a semiconductor wafer. Was found to be a hydrocarbon compound having 25 or less carbon atoms. And when the quantity of the C25 or less hydrocarbon compound adhering to the surface of a rolling bearing is 0.5 ng / mm <^2> or less, it discovered that it was hard to adversely affect a semiconductor wafer.

In addition, the organic resistivity used to clean oil components is removed by washing with pure water having an electric resistivity of 5 MΩ · cm or more as a detergent. It was found that detergents such as alkalis and acids were also removed.

The rolling bearing of this invention has little volatilization amount of a volatile component. Moreover, according to the manufacturing method of the rolling bearing of this invention, the rolling bearing with little volatilization amount of a volatile component can be manufactured.

EMBODIMENT OF THE INVENTION Embodiment of the rolling bearing which concerns on this invention, and its manufacturing method is described in detail, referring drawings. It is a partial longitudinal cross-sectional view which shows the structure of the angular ball bearing which is one Embodiment of the rolling bearing which concerns on this invention. The angular ball bearing of FIG. 48 is rotatably possible between the inner race 901 having the raceway surface 901a on the outer circumferential surface and the outer race 902 having the raceway surface 902a on the inner circumferential surface and both raceway surfaces 901a and 902a. It is formed between the retainer 904 which protects and maintains the rolling element 903, the inner ring 901, and the outer ring 902 between the several rolling elements 903 arrange | positioned, and both track surfaces 901a and 902a. The rolling element 903 includes a lubricant (not shown) disposed in the gap portion 905 provided therein.

This angular ball bearing manufactures and assembles the inner ring 901, the outer ring 902, the rolling element 903, and the retainer 904 which are bearing parts, respectively, and wash | cleans an oil component etc., and wash | cleans the said lubricant. It is obtained by filling in the space 905. This washing is performed in two stages. First, in the primary washing, processing oil and rust preventing oil attached to the surface of the rolling bearing (that is, the surface of the bearing part) using organic solvents such as petroleum benzene, white kerosene, freon replacement cleaning oil, and hydrocarbon-based organic solvents Remove oil from the back. In addition, an acid or an alkali may be used instead of the organic solvent.

In this primary cleaning, it may not be possible to remove completely until the oil content adhering to the surface of the rolling bearing enters the fine roughness of the surface. In addition, the organic solvent used by the primary washing may remain in the rolling bearing. Therefore, in the secondary washing, pure water having an electric resistivity of 5 MΩ · cm or more is used to remove residual oil components and organic solvents. Pure water having an electrical resistivity of 5 MΩ · cm or more is excellent in cleanability, and there is no fear of contaminating the rolling bearing by the pure water used itself.

Moreover, although a grease composition and lubricating oil are used as a lubricant, the thing which is hard to volatilize is used for the base oil. Examples of the base oil that is difficult to volatilize include a hydrocarbon compound having 26 or more carbon atoms (more preferably 30 or more carbon atoms), and specifically, an alkyl cyclopentane, fluorine oil, having 26 or more carbon atoms (more preferably 30 or more carbon atoms), Ester oil, ether oil, and the like. When the lubricant is a grease composition, polytetrafluoroethylene resin, urea resin, metal soap and the like are used as the thickener.

In the angular ball bearing of the present embodiment, since such cleaning is performed, the amount of the hydrocarbon compound having 25 or less carbon atoms attached to the surface of the rolling bearing is 0.5 ng / mm ² or less. Moreover, since the lubricant which has such a base oil is used, there are few volatile components from a lubricant. Therefore, since the amount of volatile components which volatilize from a rolling bearing is small, when used for a semiconductor manufacturing apparatus, it is hard to adversely affect a semiconductor wafer.

Furthermore, when forming a lubricating film made of a lubricant by an oil plating process, a lubricating oil plating process, or the like on a portion requiring lubrication such as a raceway surface of a rolling device such as a rolling bearing, the portion to be treated before forming the lubricating film Although it is preferable to wash the to-be-processed part, it is preferable to wash the to-be-processed part by the above-mentioned washing method. Then, since the to-be-processed part can be made extremely clean, it is preferable with respect to formation of a lubricating film.

In addition, this embodiment shows an example of this invention, and this invention is not limited to this embodiment. For example, in this embodiment, although the angular ball bearing was demonstrated to the example as a rolling bearing as an example, this invention is applicable to various rolling bearings of other types. For example, radial thrust bearings such as deep groove ball bearings, self-aligning ball bearings, cylindrical rolling bearings, cone rolling bearings, needle rolling bearings and self-aligning rolling bearings, and thrust ball bearings and thrust rolling bearings. Is a rolling bearing of mold.

(Example)

An Example is shown below and this invention is demonstrated further more concretely. Except that the cleaning method and the type of lubricant are different, four angular ball bearings having the same configuration as the angular ball bearing of FIG. 48 described above were prepared (see Table 3), and the volatilization amount of the hydrocarbon compound having 25 or less carbon atoms was prepared. Was measured.

Type of grease Adhesion amount ^{2 )} Primary cleaning Secondary cleaning Example One  alkali Pure water (6 MΩcm) Grease A 0.45 2  Organic solvent Pure water (10 MΩcm) Grease A 0.40 Comparative example One  Organic solvent Pure water (4.5 MΩcm) Grease A 0.60 2  alkali Pure water (6 MΩcm) Grease B 5 or more

1) Figures in parentheses indicate the electrical resistivity of pure water used.

2) Amount of the hydrocarbon compound having 25 or less carbon atoms attached to the surface of the angular ball bearing, and the unit is ng / mm ² .

The measuring method is as follows. The angular ball bearing was put in the container of the outgas collection device HM-04II of the Japan Analytical Industries, Ltd., and a purge gas was supplied at the flow volume of 20 ml / min, heating at 200 degreeC, and the volatile component was volatilized for 60 minutes. And the purge gas containing the volatile component was collected and analyzed by the gas chromatography analyzer, and the quantity of the hydrocarbon compound of 25 or less carbon atoms was measured. In addition, anthracene (14 carbon atoms) was used as a standard sample.

And it was assumed that all the detected hydrocarbon compounds having 25 or less carbon atoms were attached to the surface of the angular ball bearing, and the amount of adhesion per unit area (unit: ng / mm ² ) was calculated. The results are shown in Table 3. Here, the lubricant used for the bearings of Examples 1, 2 and Comparative Example 1 is vacuum fluorine grease YVAC3 manufactured by Solvay Rexsys Co., Ltd., and is indicated as grease A in Table 3. In addition, the lubricating agent used for the bearing of the comparative example 2 is fluorine grease KPM for atmospheric pressure of the Seiko Co., Ltd. product of Japan, and it is indicated with grease B in Table 3.

As can be seen from Table 3, the bearings of Examples 1 and 2 were subjected to secondary cleaning using pure water having an electrical resistivity of 5 MΩ · cm or more as a detergent after the primary cleaning using an alkali or an organic solvent as a detergent. Since the lubricating agent based on the hydrocarbon compound with a C26 or more hydrocarbon compound is used, the quantity of the C25 or less hydrocarbon compound adhering to the bearing surface was 0.5 ng / mm <^2> or less.

On the other hand, although the bearing of the comparative example 1 uses the lubricating agent based on a hydrocarbon compound with 26 or more carbon atoms, since it carries out the secondary washing | cleaning using pure water with an electric specific resistance of less than 5 M (ohm) * cm as a detergent, it is a bearing. The amount of the hydrocarbon compound having 25 or less carbon atoms adhering to the surface of the was more than 0.5 ng / mm ² . In addition, although the bearing of the comparative example 2 performs the secondary washing | cleaning which used pure water of 5 M (ohm) * cm or more as a detergent, since the bearing was equipped with the lubricant using the base oil containing the hydrocarbon compound of 25 or less carbon atoms, the bearing surface The amount of the hydrocarbon compound having 25 or less carbon atoms attached to the bond was more than 0.5 ng / mm ² .

The rolling bearing of this invention can be used suitably for the semiconductor manufacturing apparatus etc. which are required to have a small amount of volatile components.

The thin film bearing of this invention can be used suitably for the robot etc. for semiconductor manufacturing apparatuses.

Claims (26)

delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete The rolling element is opened at an axial end with a plurality of rolling elements 3 arranged to be rotatable between the inner ring 1, the outer ring 2, the inner ring 1 and the outer ring 2, and an axial end thereof. It is provided with the resin retainer 4 which has the pocket which protects and keeps rolling possible, A thin film bearing that satisfies the formula (D-d) /d≦O.187 (where D is the bearing outer diameter and d is the bearing inner diameter). The retainer 4 is constituted by one or more plate members 5 annularly arranged between the inner ring 1 and the outer ring 2, In the plate-like member 5, in which both plate surfaces 5b are disposed toward the inner ring 1 and the outer ring 2, respectively, When the length of the plate-shaped member 5 in the longitudinal direction is L, the thickness of the plate-shaped member is t, the inner diameter of the outer ring is Di, and the outer diameter of the inner ring is d ₀ , t <0.5 (Di ² -L ² ) Thin film bearing characterized by satisfying the relationship of ^1/2 -0.5d _O. The method of claim 21, The chamfered part of the said plate-shaped member is arrange | positioned so that both plate surfaces 5b may be arrange | positioned toward the said inner ring 1 and the outer ring 2, respectively, and the thickness of the said plate-shaped member becomes thin gradually toward the circumferential end surface 5a. (5c) is formed, The circumferential end face 5a of the plate-like member 5 and the chamfer 5c intersect each other in a range of 90 ° or more and less than 135 °, and between the circumferential end face 5a and the chamfer 5c. An edge portion formed at a boundary of the edge portion does not contact the inner ring 1 and the outer ring 2, and an edge portion formed at a boundary between the plate surface 5b of the plate member 5 and the chamfer 5c is formed. The thin film bearing, characterized in that the contact with the inner ring (1) or the outer ring (2) during the rotation of the thin film bearing. The method of claim 21 or 22, A thin film bearing characterized by covering at least one of the raceway surface of the inner ring (1), the raceway surface of the outer ring (2), and the raceway surface of the rolling element (3) with any one of the following three types of lubricating film. (1) A lubricating film containing a fluorine-containing polymer having a functional group and a perfluoropolyether (2) A lubricating film containing a fluorinated polymer having a functional group, a perfluoropolyether, and a fluororesin (3) A lubricating film containing a lubricating oil containing an alkylated cyclopentane or polyphenyl ether and a fluororesin. The method of claim 21 or 22, The retainer 4 comprises a through hole 14, wherein the through hole 14 is located between pockets 6 adjacent to each other among pockets 6 formed at intervals along the circumference of the retainer 4. The thin film bearing, characterized in that formed in the pillar (10) extends in the axial direction of the retainer (4). The method of claim 24, The through hole (14) is a thin film bearing characterized in that it is a hole opening at an axial end of the holder (4) or a hollow hole not opening at the axial end. The method of claim 22, The chamfered portion (5c) of the plate-shaped member (5) is a thin film bearing, characterized in that it is curved and continuously connected to the circumferential end surface (5a) and the plate surface (5b).

Images